Problem 14
A carbon atom has a mass number of \(12 .\) How many protons and how many neutrons does it have? A) 6,6 C) 6,12 ?) 12,12 D) 12,6
Problem 14
How is an element different from a compound?
Problem 15
On Earth, oxygen usually exists as which of the following? A) solid C) liquid B) gas D) plasma
Problem 15
How do homogeneous mixtures differ from heterogeneous mixtures?
Problem 17
An isotope known as iodine-131 has 53 protons. How many neutrons does it have? A) 78 C) 68 B) 53 D) 184
Problem 18
Which of the following are electrically charged? A) molecule C) isotope B) solution D) ion
Problem 19
Which of the following is not a physical property of water? A) transparent B) colorless C) higher density in the liquid state than in the solid state D) changes to hydrogen and oxygen when electricity passes through it
Problem 20
If an atom has no electric charge, what can be said about the number of protons and electrons it contains?
Problem 21
An aluminum lid has a mass of \(6.5 \mathrm{~g}\). It has a volume of \(2.4 \mathrm{~cm}^{3}\). Calculate the density of aluminum in grams per cubic centimeter.
Problem 21
Carbon has six protons and nitrogen has seven protons. Which has the greatest number of neutrons-carbon-13, carbon-14, or nitrogen-14?
