2. Atoms & Elements

Which of the following best describes the composition of ozone in the stratosphere above the Earth?

Protons have what type of charge?

Which of the following is the number of protons in a krypton (Kr) atom?

How many electrons are present in the oxide ion, O^{2-}?

In an atom, where are electrons most likely to be found?

How many protons and electrons are present in a neutral atom of strontium (Sr)?

Which of the following best defines an atom?

Which of the following is a substance that is made up of only one type of atom?

How many protons are present in a neutral atom of calcium?

Which of the following particles are found in the nucleus of an atom?

Which of the following statements about krypton (Kr) is correct?

How many atoms of oxygen are present in one molecule of oxygen gas (O_2)?

How many protons are present in an atom of bismuth?

Atoms seldom exist as independent particles in nature because:

What is the maximum number of electrons that can be contained within the n = 2 shell of an atom?