Answer: The first ionization energy for the first five elements of Group 15 decreases.
Explanation:
Ionization energy is defined as the energy required to remove an electron from the outermost shell of an isolated gaseous atom. It is represented as
Ionization energy decreases as we move down the group. This happens because the number of shells increases as we move down the group. The electrons are added in the new shell around the nucleus.
This results in the shielding of outermost electrons more from the inner ones, which decreases the attraction between the outermost electrons and the nucleus. Hence, the removal of electron from the outermost shell becomes easy and requires less energy.
Hence, the first ionization energy for the first five elements of Group 15 decreases.
The percent by mass of chlorine in NaCl is 60.68 % of chlorine
calculation
mass % of chlorine =mass of chlorine /mass of NaCl x 100
from periodic table the mass of cl= 35.5 g/mol
that of of Na = 23 g/mol
The mass of NaCl is therefore = 35.5 g/mol + 23 g/mol =58.5 g/mol
mass % is therefore= (35.5 / 58.5 x 100) =60.68 %
In the given question, 60.66% is the percent by mass of chlorine in NaCl.
Mass is a physical property of matter that measures the amount of substance in an object. It is typically measured in grams (g) or kilograms (kg).
The molar mass of NaCl is 58.44 g/mol. The molar mass of chlorine is 35.45 g/mol. The formula of NaCl indicates that there is one chlorine atom for every sodium atom. Therefore, the mass of chlorine in NaCl is 35.45 g/mol.
To calculate the percent by mass of chlorine in NaCl, we need to divide the mass of chlorine by the total mass of NaCl and multiply by 100. This can be expressed as follows:
Percent by mass of chlorine = (mass of chlorine/mass of NaCl) × 100
Substituting the values, we get:
Percent by mass of chlorine = (35.45 g/mol/58.44 g/mol) × 100
= 60.66%
Therefore, the percent by mass of chlorine in NaCl is 60.66%.
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The reactant that is totally consumed during a reaction, or the limiting reagent, decides when the process comes to an end. A limiting reagent is the reactant that is used up first in a reaction. Therefore, option A is correct.
A reactant that is completely consumed at the end of a chemical reaction is known as the limiting reagent. Since the reaction cannot proceed without this reagent, the amount of product that can be produced is constrained.
The limiting reactant is the one that is consumed first and sets a limit on the quantity of product(s) that can be produced. Calculate how many moles of each reactant are present and contrast this ratio with the mole ratio of the reactants in the balanced chemical equation to get the limiting reactant.
The terms limiting reagent and limiting agent may also be used to describe the limiting reactant.
Thus, option A is correct.
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Answer: A.) The reactant that is used up first in a reaction
Answer:
To balance the chemical equation, I'll assume the reaction is carried out under standard conditions. Here's the balanced equation:
2 N2 (g) + 5 O2 (g) → 4 H2O (l) + 4 NO3- (aq)
Explanation:
To balance the number of nitrogen (N) atoms, we need 2 nitrogen molecules (N2) on the left side. This gives us a total of 4 nitrogen atoms on the left side.
To balance the number of oxygen (O) atoms, we need 5 oxygen molecules (O2) on the left side. This gives us a total of 10 oxygen atoms on the left side.
On the right side, we need 4 water molecules (H2O) to balance the hydrogen (H) atoms. This gives us a total of 8 hydrogen atoms on the right side.
Finally, to balance the oxygen (O) atoms on the right side, we need 4 nitrate ions (NO3-) since each nitrate ion contains one nitrogen and three oxygen atoms. This gives us a total of 12 oxygen atoms on the right side.
Now the equation is balanced with 4 nitrogen atoms, 10 oxygen atoms, 8 hydrogen atoms, and 4 nitrate ions on both sides.
2: Chlorine free radicals are produced in the upper atmosphere when ultraviolet radiation interacts with chlorofluorocarbons (CHCs). The free radicals catalyze the conversion of ozone to oxygen. How is this catalysis harmful to humans
1. By using less energy, reactions that are catalysed are also more sustainable, and therefore better for the environment.
2. By catalysing the conversion of ozone into oxygen, the ozone layer sees a reduction, also reducing the amount of protection from direct UV rays given to humans and other forms of life by the ozone layer.