1. An atom of silicon has a mass number of 28 and an atomic number of 14. How many protons and how many neutrons are in this atom? Show your calculation.

An increase in the temperature of reactant causes an increase in the rate of reaction. Which of the following is the best explanation?

3. When atoms combine to form molecules, a (blank) change has occurred.

What is the amount of product that you get when you perform an experiment called

Which of the following happens when chlorine forms an ion? A. It gains an electron and has an octet in its outer shell. B. It loses an electron and has an octet in the next-lowest energy level. C.

An obese man was discovered in his air-conditioned hotel room sitting in a chair in front of the television. The air conditioner was set for 65 degrees Fahrenheit. When the coroner arrived, the man's body exhibited rigor in his upper body only.

If enough heat is added to a substance, electrons begin to separate from the atomic nuclei. Which process does this describe? A. A solid turning into a liquid B. A plasma turning into a gas C. A gas turning into a plasma D.

What is the percent of H2O in a sample of a hydrate whose mass is 1.1290 g if the mass of water in the sample was 0.1660 g?

Why does conduction occur in solids and liquids easier compared to gases? Because the particles in gases are closer together and move slower Because the particles in gases are farther apart and move faster.

Write a balanced equation for the combustion of gaseous methane (CH4), a majority component of natural gas, in which it combines with gaseous oxygen to form gaseous carbon dioxide and gaseous water.

Pedro listed characteristics of two types of protists in a chart. Two Groups of Protists X Y Often multicellular Are usually autotrophic Include euglenoids Are heterotrophs Reproduce using spores Include different molds Which headings best complete