Answer:
They are jogging side by side at 5 m/s
Let's distinguish between the concepts of speed and velocity:
speed is a scalar quantity: a scalar quantity has a magnitude but not a direction, it's simply a number which doesn't indicate the direction of movement;velocity is a vector: a vector indicates both a magnitude (it has a scalar quantity) and a direction.The first condition we have here is the fact that two people have the same speed, this means they are moving at the same rate of change of distance. The second condition must be met as well, if we wish them to have the same velocity, this means they should be moving in the same direction, let's say, along the positive or negative x-axis, but not in opposite directions.
The kinetic energy within molecules of an object ________ when heat is added.
Answer:
Vibrates (combines)
Explanation: addition of heat to a particle causes the ions to become charged (energized) and this results to vibration and Interaction between the Molecules and the walls of the object
Science Chemical compound formula
Answer:
NaCl (common salt)
Explanation:
it is called sodium chloride
A chemical formula is a symbolic representation of a compound's composition. It uses element symbols and subscripts to denote the types of atoms present and their quantities. The formula H₂O represents water, while H₂SO₄ represents sulfuric acid, with N₂O₃ being the formula for dinitrogen trioxide.
A chemical formula represents a substance using symbols for its constituent elements and subscripts to show the number of atoms of each element in the compound. For example, the compound water has a chemical formula of H₂O, indicating it contains two hydrogen atoms and one oxygen atom. Another example is sulfuric acid, a widely produced chemical with a formula of H₂SO₄, showing it is composed of two hydrogen atoms, one sulfur atom, and four oxygen atoms. The naming convention for covalent compounds like dinitrogen trioxide involves using prefixes to denote the number of each type of atom present; thus, N₂O₃ denotes two nitrogen atoms and three oxygen atoms.
Which element has 7 valence electrons
Answer:
Halogens have 7 valence electrons.
Explanation:
They are the most active non-metals including fluorine, chlorine, bromine, iodine, and astatine
Which of these statements is correct about P and S seismic waves? (2 points) Question 40 options: 1) Both P and S waves travel along Earth's surface and their amplitude decreases with depth into Earth. 2) Both P and S waves travel with the same speed through Earth and their amplitude increases with time. 3) P waves are radiated along a single direction but S waves are radiated along all directions. 4) P waves change the volume of the medium through which they travel but S waves do not change the volume of the medium
Answer:
3
Explanation:
Primary waves are radiated along a single direction, but secondary waves are radiated along all directions. That is why the P waves can take place in almost all mediums such as solid, liquid and air, unlike the S waves that are transverse and only travel through solid mediums
what is the indication that tells us what charge a transitional metal has since they dont have a set trend
Answer:
Roman numbering in IUPAC naming system
Explanation:
This is quite an open question. Let's firstly separate the periodic table into two standard groups: group A elements and group B elements (transition metals).
The charge (or the oxidation state) of an element in group A can be identified by the group number. For example, group 1A elements would always have a charge of +1, as they have only one valence electron to lose.
Similar trend applies to group 2A: each element in that group would have a charge of +2, as each atom has 2 valence electrons to lose to become a cation.
You will notice that this is true fro group 3A and group 4A as well. Now, since an octet is the desired state for any species, starting with group 5A, it's easier to gain 3 electrons for species than lose 5 electrons to obtain an octer, meaning we'd expect -3 oxidation state for group 5A elements, -2 oxidation state for group 6A elements and -1 oxidation state for group 7A elements.
Notice that in the majority of cases, this is the standard trend and we'd generally only have one predominant oxidation state.
Considering group B, the transition metals, most of them have several oxidation states. That's why we usually memorize the ones which only have one oxidation state (such as zinc, silver) and in any other case when a transition metal has several oxidation states, they're identified in the name by using Roman numbering system.
Let's look at an example. Assume the problem states we have a salt which is iron chloride. This would be an improper name, as iron has two oxidation states: +2 and +3. That's why we have the rules of IUPAC naming to avoid ambiguity. If we had iron with an oxidation state of +2, we'd call the salt iron(II) chloride. An oxidation state of +3 would indicate iron(III) chloride.
To summarize, the main key of knowing the charge of a transition metal in a compound is to follow the IUPAC naming rules.
an element x atomic number 3,relative atomic number 6.94 and consists of two isotopes of mass numbers 6 and 7 respectively.
What is the mass number of the more abudant isotope of x?
Answer:
7
Explanation:
Atomic number of X = 3
Atomic mass of X = 6.94 amu
1st isotope atomic mass = 6 amu
2nd isotope atomic mass = 7 amu
Which is more abundant isotope = ?
Explanation:
we know there are two naturally occurring isotopes of given element X, X-6 and X-7.
First of all we will set the fraction for both isotopes
x for the isotopes having mass 6
1-x for isotopes having mass 7
The average atomic mass of X = 6.94 amu
we will use the following equation,
6x + 7 (1-x) = 6.94
6x + 7 - 7x = 6.94
6x- 7x = 6.94 - 7
-1x = -0.06
x= -0.06/-1
x= 0.06
0.06 × 100 = 6%
6% is abundance of X-6 because we solve the fraction x.
now we will calculate the abundance of X-7.
(1-x)
1-0.06 =0.94
0.94 × 100= 94%
94% for X-7.
Would it be A or C???????? Helppp
Answer:
c
Explanation:
Answer:
A. One that is not a fossil fuel
Explanation:
"Alternative fuel" is a technical term used in the fuel industry. It refers to fuels that that are not fossil fuels (like coal, oil, and natural gas).
B. is wrong. A fuel that hasn't been developed yet is not of much use.
C. is wrong. A homeowner may consider wood as an alternative fuel in case there is no electricity to power an oil furnace, but that is not the technical meaning of the term.
D. is wrong. An alternative fuel should use renewable resources.
Select all the correct answers.
Which natural methods remove CO2 from the atmosphere?
respiration of living organisms
photosynthesis by plants
evaporation of ocean water
absorption of CO2 from the atmosphere by ocean water
melting of glacial ice
Answer:
The natural method of removal of CO2 is
Photosynthesis by plants
Absorption of CO2 from the atmosphere by ocean water
Melting of glacial ice
Explanation:
Respiration of living organism : In this process, Oxygen is consumed(removed) and Carbon dioxide(CO2 ) is formed.So it forms CO2 .
Photosynthesis by plants: Green plant containing. prepare their food in presence of sunlight by using CO2 , water ,Hence CO2 is removed from atmosphere.
Evaporation of ocean water : It increases the level of CO2 in atmosphere. The heating of oceans surface Degassed CO2 to atmosphere.
Absorption of CO2 from the atmosphere by ocean water : the plants under the oceans needs CO2 to carry out photosynthesis .Hence oceans absorbs CO2 from atmosphere .Here, CO2 is removed from atmosphere.
Melting of glacial ice : Glacial ice absorb carbon dioxide because it does not have organism respiration (organisms releasing CO2 ).They capture large amount of CO2 and called CO2 sinks.(Remove CO2)
Answer:photosynthesis by plants
absorption of CO2 from the atmosphere by ocean water
Explanation:
Photosynthesis involves the combination of CO2 with water to form glucose and subsequently complex carbohydrates. Plants constitute a very important sink for carbon IV oxide in nature. Secondly, oceans absorb carbon IV oxide to maintain the concentration of bicarbonate in the water. These are two important natural methods that remove CO2 from the environment.
Casey remembers that molecular motion increases as temperature increases. Identify what effect increased molecular motion.
A) Increasing the molecular motion reduces the solubility.
B) Increasing the molecular motion decreases the reaction rate
C) Increasing the molecular motion divides the activation energy
D) Increasing the molecular motion increases collision frequency.
D
Molecular motion increases as temperature increases and therefore increasing the molecular motion increases collision frequency.
Explanation:
When a substance is heated, its molecules gain increased kinetic energy even as the substance increases in temperatures. With higher kinetic energy, this means the molecules are moving more rapidly and hence collision between the molecules will be more frequent and of higher energy. It is these high energy collisions that cause the molecules to move further away from each other with increased temperatures (why substances expand).
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Answer: Your answer would be D
Explanation: This is because whenever the collision increases the molecular motion increases with it.
atom with the largest atomic radius in group 18
Answer:
Radon
Explanation:
Group eighteen elements are called noble gases. This group includes helium, neon, argon, krypton, xenon and radon.
Radon is present at the last of this column.
Atomic radii trend along group:
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus.
Thus radon has largest atomic radius.
Answer:Rn =Radon
Explanation:
when do d orbitals start getting filled
Answer & Explanation:
D orbitals begin filling with electrons after the orbital found in the 4s sublevel is filled. This occurs because the d sublevel is first found in the.
Answer:
Interesting question.
Explanation:
D orbitals begin filling with electrons after the orbital found in the 4s sublevel is filled.
Have a good day
Question is attached below!
Answer:
263 g
Explanation:
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created not destroyed in a chemical equation.
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Thus in given example the mass of reactant is 263 g therefore the mass of product would be 263 g.
Another example:
In given photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass
what happens to the properties of substances during a chemical reaction?
Explanation:
In a chemical reaction, only the atoms present in the reactants can end up in the products. Also, In a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.
Given the reactants of HNO3 + LiOH → predict the products *
Answer:
Lithium nitrate and water are product of given reaction.
Explanation:
Word equation:
Nitric acid + lithium hydroxide → Lithium nitrate + water
Chemical equation:
HNO₃ + LiOH → LiNO₃ + H₂O
The given reaction is balanced. There are two hydrogen, four oxygen, one lithium and one nitrogen atoms are present on both side of equation.
This reaction completely follow the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Lamp, toaster, and a fan
Each device shown on this drawing is plugged into an electrical outlet. Each device converts this electricity into three different types of energy.
Question:
Identify and describe the energy transformations shown with each device in this drawing. Write a separate and complete sentence for each identified energy transformation.
Answer: Light, Thermal, Kinetic
Explanation:
The lamp converts the electric energy to light energy.
The toaster converts the electric energy to thermal energy.
The fan converts the electric energy to kinetic energy.
Good luck with your test!
Answer:
it is what every the one above said
Explanation:
1. What is the density of a 20 gram of 40 ml liquid?
2. Which liquid would be on top one when one liquid has a density of 1.0
g/cm or .88 g/cm'?
3. Why is the solid phase denser than liquids or gases?
4. How can you witness
5. Balance this equation: H+ = H2O
6. What is the ratio of OH-to H+ in water?
7. What safety equipment should you wear for chemicals?
8. What should you do if chemicals get in your eye during lab?
9. List facts about each of the element group families from 1-18
10. List the ways that matter is measured
11. Define condensation
12. State the kinetic theory of particle movement
Answer:
1. [tex]0.5 g/mL[/tex]
2. [tex]0.88 g/cm^3[/tex]
3. It has the greatest mass to volume ratio
4. Incomplete
5. [tex]H^+ (aq)+OH^-(aq)\rightleftharpoons H_2O (l)[/tex]
6. 1
7. Gloves, goggles, coat, mask
8. Flush with tap water for at least 15 minutes
9. The facts are listed below
10. Mass and volume
12. All matter consists of moving particles, the degree of their movement is directly proportional to their kinetic energy
Explanation:
1. In order to solve for density, we should know that density is the ratio between mass and volume of a liquid. In this case, we're given both measures: given mass of m = 20 g and volume of V = 40 mL, we may simply apply the equation of density described here:
[tex]d=\frac{m}{V}[/tex]
Substituting the variables, we obtain:
[tex]d=\frac{m}{V}=\frac{20 g}{40 mL}=0.5 g/mL[/tex]
2. Given a mixture of several liquids, it's important to understand that liquids with a greater density will tend to form a bottom layer of a solution, while liquids with a lower density will tend to form a top layer of a solution. Here we have a liquid with a density of [tex]d_1 = 1.0 g/cm^3[/tex] and another liquid with a density of [tex]d_2 = 0.88 g/cm^3[/tex]. Notice that [tex]d_1[/tex] > [tex]d_2[/tex].
This implies that the liquid with a density of [tex]0.88 g/cm^3[/tex] would be on top, as its density is lower than the density of the other liquid with a density of [tex]1.0 g/cm^3[/tex].
3. The solid phase is not always, but typically denser than liquids or gases. There are some exceptions to this rule, for example, ice, a solid phase of water, is less dense than liquid water.
However, for the majority of cases this statement is true. Remember that solid phases are the most ordered phases with atoms being packed closely to each other. In liquids, atoms are more dispersed with distances between them being greater than those in solids. Similarly, gases have the greatest distances between gas atoms among all three phases.
Since density is directly proportional to mass, let's say we take the same volume of a solid, a liquid and a gas. For the same volume, since we'll have a greater number of solid atoms than for a liquid or a gas (because solid atoms are more closely packed with lower average distances between the atoms), the mass to volume ratio will be the greatest for solids.
4. This seems to be an incomplete question.
5. In order to balance the following ionic equation, we need to follow the mass and charge balancing rules. Firstly, expand a water molecule showing the individual parts of it:
[tex]H-OH[/tex]
Secondly, notice that we need to add a hydroxide anion to the proton, so that we obtain the same number of protons and hydroxide anions on the left side, as well as the number of hydrogen and oxygen atoms on the right. This way, the net charge on the left hand side (0) and the net charge on the right hand side (0) are equal, so the charge is balanced as well. We obtain:
[tex]H^+ (aq)+OH^-(aq)\rightleftharpoons H_2O (l)[/tex]
6. We should be familiar with the ionization constant of water in the context of this problem. It is defined as the product between the hydronium ions and hydroxide ions and is a constant number at some given temperature. For pure water, the concentration of hydronium ions is balanced by the concentration of hydroxide anions to yield a neutral pH value, meaning the ratio of one with respect to the other would be 1.
For example, at room temperature, the ionization constant of water is defined as:
[tex]K_w=[H^+][OH^-]=10^{-14}[/tex]
Since we have pure water:
[tex][H^+]=[OH^-]=\sqrt{10^{-14}}=10^{-7}[/tex]
Then the ratio is:
[tex]\frac{[H^+]}{[OH^-]}=\frac{10^{-7}}{10^{-7}}=1
7 to 12. The questions are explained in the file attached.
Two basic properties of the gas phase are
please help with chemistry work
Answer:
Explanation:
14:
a) Shared pairs = 6
per shared pair between each C-H bond.
and two shared pair between C=C thus total shared pairs are 6
a) Lone pairs = 0
b) Single bonds = 4
Double bonds = 1
Triple bonds = 0
c) Formula = C₂H₄
Name = Ethene
d) Lewis structure = given structure is also Lewis structure.
13:
a) Shared pairs = 3
a) Lone pairs = 2
b) Single bonds = 0
Double bonds = 0
Triple bonds = 1
c) Formula = N₂
Name = Dinitrogen
d) Lewis structure = given structure is also Lewis structure.
Bridges and automobiles are either painted or coated with zinc. Why is it not electroplated?
Final answer:
Zinc is used to protect bridges and automobiles from corrosion because it is more easily oxidized than iron, providing sacrificial protection. Electroplating is not commonly used because it results in a thinner and less durable zinc layer.
Explanation:
Zinc is often used to protect bridges and automobiles from corrosion because it is more easily oxidized than iron. This means that even if the zinc coating gets scratched, the zinc will still oxidize before the iron, providing a sacrificial protection. While electroplating could be an option, it is not commonly used because it results in a thinner and less durable zinc layer compared to other coating methods.
Which is an intensive property of a substance?
density
volume
length
mass
Mark this and retum
Save and Exit
Submit
Answer:
Density.
Explanation:
That is density because it does not depend on the amount of the substance.
A small container of water boils at 100°C. The boiling point increases by 1°C for every 12 g of salt dissolved in the water. Determine the new boiling point of the water after 48 g of salt is dissolved into it
NaOH + H2CO3 → Na2CO3 + H2O
Balance Chemical Eguation
Answer:
2NaOH + H2CO3 —> Na2CO3 + 2H2O
Explanation:
To balance the equation NaOH + H₂CO₃ → Na₂CO₃ + H₂O, introduce a coefficient of 2 before NaOH and H2O resulting in the balanced chemical equation 2NaOH + H₂CO₃ → Na₂CO₃ + 2H₂O
To balance the chemical equation NaOH + H2CO3 → Na2CO3 + H2O, we need to ensure that the number of atoms of each element on the reactant side is equal to the number of atoms of that element on the product side. The original equation is already balanced with respect to carbon and oxygen, but not with sodium and hydrogen. By changing the coefficient for NaOH to 2, the equation becomes balanced for sodium. Hence, the balanced chemical equation is:
2NaOH + H₂CO₃ → Na₂CO₃ + H₂O
Now equation is imbalanced with oxygen and hydrogen. To balance the equation with respect to oxygen and hydrogen coefficient 2 is introduced before H2O. Hence, the balanced chemical equation is:
2NaOH + H₂CO₃ → Na₂CO₃ + 2H₂O
The final balanced chemical equation is 2NaOH + H₂CO₃ → Na₂CO₃ + 2H₂O
A sample of wood from the remains of a ship was found to contain 40.0% of C-14 as of ordinary wood found now. If the half-life period of C 14 is 5770 years, find the number of years elapsed. (Round your answer to the nearest whole number)
Answer:
7628 y
Explanation:
Carbon-14 is radioactive and it follows the first-order kinetics for a radioactive decay. The first-order kinetics may be described by the following integrated rate law:
[tex]ln(\frac{[A]_t}{[A]_o})=-kt[/tex]
Here:
[tex][A]_t[/tex] is the mass, moles, molarity or percentage of the material left at some time of interest t;
[tex][A]_o[/tex] is the mass, moles, molarity or percentage of the material initially, we know that initially we expect to have 100 % of carbon-14 before it starts to decay;
[tex]k = \frac{ln(2)}{T_{\frac{1}{2}}}[/tex] is the rate constant;
[tex]t[/tex] is time.
The equation becomes:
[tex]ln(\frac{[A]_t}{[A]_o})=-\frac{ln(2)}{T_{\frac{1}{2}}}t[/tex]
Given:
[tex]\frac{[A]_t}{[A]_o} = \frac{40.0 %}{100.0 %}[/tex]
[tex]T_{\frac{1}{2}} = 5770 y[/tex]
Solve for time:
[tex]t = -\frac{ln(\frac{[A]_t}{[A]_o})\cdot T_{\frac{1}{2}}}{ln(2)}[/tex]
In this case:
[tex]t = -\frac{ln(\frac{40.0\%}{100.0\%})\cdot 5770 y}{ln(2)}[/tex]
[tex]t = 7628 y[/tex]
Select all the correct answers.
Sully works as a geologist in the southwestern United States. He plans to choose an unstable isotope to find the absolute age of a rock sample. Which two aspects must he consider before making his choice?
There should be a sufficient amount of the selected isotope in the rock.
The isotope should be one that decays at a very fast rate.
The isotope must not be found in any neighboring rocks.
The half-life of the isotope must be long enough to capture the age of the rock.
There should be more than one unstable isotope in the rock.
Answer:
1. There should be a sufficient amount of the selected isotope in the rock.
2. There should be more than one unstable isotope in the rock.
Explanation:
Use the proses of elimination!
Before choosing an unstable isotope, Sully must consider the half-life of the isotope, which must be long enough to capture the age of the rock, and the sufficiency of the amount of the chosen isotope present in the rock. The rate of decay, presence in neighboring rocks or existence of more unstable isotopes are not primary concerns.
Explanation:Sully, a geologist, should consider the following two aspects before choosing an unstable isotope for determining the absolute age of a rock sample. First, the isotope must have a long enough half-life to accurately capture the age of the rock. For example, if the rock is several million years old, the isotope chosen should have a half-life in that ballpark to provide effective dating. Second, there should be a sufficient amount of the chosen isotope present in the rock. The abundance of the isotope is crucial, as too small an amount may result in inaccurate dating. On the contrary, the isotope doesn't necessarily need to decay at a fast rate or be absent in neighboring rocks to produce accurate results. Also, having more than one unstable isotope in the rock isn't a mandatory requirement.
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Why does mixing reactants in different mole ratios affect the amount of the product and the amount of each reactant that is left over?
Answer:
Because of the reaction stoichiometry (detailed information given below).
Explanation:
Well, reaction stoichiometry determines relationships between reactants and products in a chemical reaction. For example, if the relationship between reactants and/or products is 1 to 1 (e.g. CO + H2O => CO2 + H2), the product is produced as much as the limiting reactant(s) (which is less than the other one in amount) consumed. For example, if 3 moles CO mixed with 0.5 moles of O2 (so O2 is limiting reactant in this case), 0.5 CO2 and 0.5 H2 are produced and 2.5 moles of CO and 0 moles of O2 (because all of O2 consumed) are left over. So, it can be concluded that the reaction stoichiometry has a direct relationship with the amount of the product and the amount of each reactant left over.
The amount of product and leftover reactants in a chemical reaction is determined by the mole ratios of the reactants, based on stoichiometry.
The amount of product and leftover reactants in a chemical reaction depend on the mole ratios of the reactants.
This concept is part of stoichiometry, which examines the numerical relationships between reactants and products in a balanced chemical equation.
Typically, one reactant will be completely consumed first, known as the limiting reactant, determining the amount of product formed, while the other reactants may be left over in varying amounts.
First, identify the balanced chemical equation for the reaction.Determine the mole ratios of the reactants to the products using the coefficients in the balanced equation.Identify the limiting reactant by comparing the initial amounts of reactants given and using the mole ratios.Calculate the expected amount of product formed based on the limiting reactant’s quantity.Determine the amount of any excess reactant by subtracting the amount that reacted from the initial amount.For example, in the reaction between hydrogen gas (H₂) and oxygen gas (O₂) to form water (H₂O), mixing 2 moles of H₂ with 1 mole of O₂ would use up all reactants perfectly, producing 2 moles of H₂O. However, if we mixed 3 moles of H₂ with 1 mole of O₂, H₂ would be in excess and only 2 moles of H₂ would react, leaving 1 mole of H₂ unreacted.
why does an ionic bond form between magnesium and oxygen?
Answer:
Mg loses two electrons to have an octet. Oxygen gains two electrons to have an octet. The ionic bond between ions results from the electrostatic attraction of opposite charges. The final formula of magnesium oxide is MgO.
Explanation:
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Which statement best describes how genetic information is passed to the offspring of Astrammina rara?
A. Half of the genetic information comes from one parent.
B. The genetic information comes from the egg.
C. All of the genetic information comes from one parent.
D. The genetic information comes from the sperm.
Answer:
The correct option is C) All of the genetic information comes from one parent.
Explanation:
The description in the paragraph tells that Astrammina rara are unicellular organisms and their offspring born are identical to the parent cell.
Asexual reproduction can be described as a method of reproduction in which a parent cells produces two offsprings which are identical to the parent cell. Asexual reproduction is the common mode of reproduction in unicellular organisms.
Hence, the description shows that Astrammina rara reproduce by this method and hence all of the information will arise from one, single parent.
the T 1/2 of a certain radioisotope is 4 weeks what fraction of the original isotope remains after 12 weeks
Answer:
The fraction of original isotope remaining after 12 weeks is 1/8 (0.125)
Explanation:
The half life of the radio-isotope = 4 weeks =[tex]t_{\frac{1}{2}}[/tex]
After n half lives, the fraction of original isotope remaining = [tex]\frac{1}{2^{n}}[/tex]
In 12 weeks, the number of half lives = 12/4 = 3 half lives
The fraction of original isotope remaining = [tex]\frac{1}{2^{3}}=\frac{1}{8}[/tex]
Hence, after 12 weeks, fraction of original isotope remaining is 1/8 (0.125)
Which groups in the main group have a lower electronegativity than D block elements
Answer:
S-block
Explanation:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus thus electronegativity increases.
As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required.
S-block is present on left side of periodic table while d-block is on the right side thus as we move from s to d block electronegativity increases,
in an experiment magnesium ribbon was heated in air the product formed was found heavier than original ribbon.potassium manganate(vii)was heated im air and product formed was found lighter.explain different observations made
Answer:
1: due to difference in reactivity and melting point
2 during the reaction both combine with oxygen in this case magnesium remain solid but some potassium vaporise
The burning of Magnesium ribbon in the air is a chemical change.
What are the observations made?Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray solid that shares many physical and chemical properties with the other five alkaline earth metals.Magnesium is a silvery-white metal.Magnesium burns in the air in the presence of oxygen in the form of Magnesium oxide.2Mg (s) + O2 (g) ⇒ 2MgO (s)
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