An atom consists of a central nucleus with positively charged protons and neutral neutrons. Negatively charged electrons revolve around the nucleus along electronic shells. A metal atom has the tendency to lose electrons from the outermost electronic shell to form a positive ion known as cation. In a cation, the number of electrons is less than the protons in the nucleus. As a result, electrons are attracted towards the nucleus by a strong force of attraction. This makes metal ions smaller than their corresponding neutral atoms.
(Ans) (b) smaller than
A nonmetal atom usually gains electrons to form a negative ion or anion. In an anion the number of electrons is more. As a result, electrons start to repel with each other and the electrons spread out. This increases the size of anions. For this reason, nonmetal ions are typically larger than their corresponding neutral atoms.
(Ans) (a) larger than
Thus problem is providing us with the mass of iron (III) oxide as 12.4 g so the moles are required and found to be 0.0776 mol after the calculations:
<h3>Mole-mass relationships:</h3>
In chemistry, we use mole-mass relationships in order to calculate grams from moles and vice versa. In this case, since we are given the mass of iron (III) oxide as 12.4 g one can calculate the moles by firstly quantifying its molar mass:

Then, we prepare a conversion factor in order to cancel out the grams and thus, get moles:

Learn more about mole-mass relationships: brainly.com/question/18311376
An inert gas will not react with either the reactants or the products, so it will have no effect on the product/reactant ratio, and therefore, it will have no effect on equilibrium.
Answer:
m = 4.7 μg
Explanation:
Given data:
density of acetone = 60.0 μg/L
Volume = 79.0 mL
Mass = ?
Solution:
Formula:
d = m/v
v = 79.0 mL × 1L /1000 mL
v = 0.079 L
Now we will put the values on formula:
d = m/v
60.0 μg/L = m/0.079 L
m = 60.0 μg/L × 0.079 L
m = 4.7 μg
So health risk limit for acetone = 4.7 μg
It would be C
2 kg x 1000 g/kg x 1mol/18.02 x 6.03 kj/mol = 669kj