Electronegativity decreases because the valence electrons are farther from the nucleus. Hence, option C is correct.
Electronegativity is a chemical property that describes the tendency of an atom or a functional group to attract electrons toward itself.
From top to bottom down a group, electronegativity decreases. This is because atomic number increases down a group, and thus there is an increased distance between the valence electrons and nucleus, or a greater atomic radius.
Important exceptions to the above rules include the noble gases, lanthanides, and actinides.
Electronegativity decreases because the valence electrons are farther from the nucleus. Hence, option C is correct.
Learn more about Electronegativity here:
#SPJ2
Answer: The number of moles that initially occupied a 250ml container remains the same when it occupied 750ml container but they are freer because the 750ml container is bigger and has more space. So the gases now occupied more space and their movement is less curtailed unlike when they were in 250ml container
b. sublimation,
c. infiltration,
d. evaporation
endothermic and exothermic reactions.
4
O Endothermic reactions absorb heat
energy while exothermic reactions
release heat energy.
O Exothermic reactions absorb heat
energy while endothermic reactions
release heat energy.
O Endothermic and exothermic reactions
absorb thermal energy.
O Endothermic and exothermic reactions
release thermal energy.
REM
The prefix exo-
applied to a che
mean energy
re
Statement-1 is the correct answer that is Endothermic reactions absorb heat energy while exothermic reactions release heat energy.
How can we distinguish between exothermic and endothermic processes?
Chemical reactions that release energy are referred to as exothermic. More energy is produced than is needed to break the bonds between the reactants when bonds are formed in the byproducts of exothermic processes.
Chemical processes that either use or absorb energy are referred to as endothermic. In endothermic reactions, more energy is absorbed when bonds in the reactants are broken than is released when new bonds are formed in the products. Since an isothermic chemical reaction uses exactly as much energy as it produces, there is no net energy change.
Therefore, the first statement is the right response.
To know more about exothermic, check out:
#SPJ1
In the reaction of hydrochloric acid and calcium carbonate, to balance the equation, the correct order of numbers would be 2 for HCl, and 1 for CaCO3, CaCl2, CO2, and H2O.
When hydrochloric acid (HCl) reacts with calcium carbonate (CaCO3) in concrete, it forms calcium chloride (CaCl2), carbon dioxide (CO2), and water (H2O). To balance this reaction, you could input the numbers: 2 HCl(aq) + 1 CaCO3(s) → 1 CaCl2(aq) + 1 CO2(g) + 1 H2O(l). This phenomenon is part of the larger concept known as a neutralisation reaction, where an acid reacts with a base to produce a salt and water. In this case, the hydrochloric acid is the acid and the calcium carbonate in the concrete is the base. This is also an example of a gas evolution reaction, as carbon dioxide gas is being produced.
#SPJ11
a) 8
40*20%
=40*20/100
=800/100
=8
The atomic weight of the unknown element, which is approximately 20% less than calcium (40 amu), is estimated to be 32 amu.
The atomic weight of an unknown element is said to be approximately 20% less than that of calcium, which has an atomic weight of 40 atomic mass units (amu). To calculate the approximate atomic weight of the unknown element, take 20% of 40 (which is 8) and subtract it from 40. The result is 32 amu (40 - 8 = 32), so the correct answer is (c) 32.
#SPJ11