McGraw Hill - Chemistry - Chapter 2 Test

Front

What is the atomic number of phosphorus (P)?

Back

15

Front

How do you calculate the mass of magnesium oxide produced when magnesium reacts with oxygen?

Back

By adding the mass of magnesium (0.243 g) and the mass of oxygen (0.160 g), the total mass of magnesium oxide produced is 0.403 g.

Front

Which element is very reactive because it needs one more electron to satisfy the octet rule?

Back

Iodine is very reactive due to its need for one more electron.

Front

What is the atomic number of an isotope of carbon that has 6 protons?

Back

6

Front

How many valence electrons does a magnesium atom have?

Back

2

Front

What is the definition of the octet rule in chemistry?

Back

The octet rule states that atoms tend to gain, lose, or share electrons to achieve a full outer shell of eight electrons.

Front

What is the significance of atomic number in an element?

Back

The atomic number indicates the number of protons in the nucleus of an atom, which determines the element's identity.

Front

What is the relationship between protons and neutrons in an isotope?

Back

An isotope has the same number of protons but a different number of neutrons compared to other isotopes of the same element.

Front

How do you determine the number of valence electrons in an element?

Back

The number of valence electrons can be determined by the group number of the element in the periodic table.

Front

What is the formula for calculating the mass of a compound formed from its reactants?

Back

The mass of the compound is equal to the sum of the masses of the reactants.