1. What is the percent composition of CaCO₃? Show your work.

2. What is the mass of sodium in 50 grams of salt? Show your work.

3. What two general products do combustion reactions create?

4.

An engineer uses aluminum to build an airplane rather than composite materials that are lighter and stronger. He does this because he is concemed about the composite materials and how suddenly they can fail. This is an example of A.

For the following hypothetical reaction: 3A+9B-->5C How many moles of B will you need to convert 2 moles of A into as many moles of C as possible? Enter just the number; not the number and units

Which most likely would be a new social issue resulting from the installation of a dam? A. Antibiotic resistance B. Habitat destruction C. Greater exposure to radiation D. Increase in biodiversity

A reaction produces 0.415 mol of H2O. How many molecules of water are produced?

Do atoms get bigger or smaller as you read from left to right

What size container do you need to hold 0.0459 mol of N2 gas at stp

What happens when two or more atoms react?

If cobalt metal is mixed with excess sulfur and heated strongly, a sulfide is produced that contains 55.06% cobalt by mass. Calculate the empirical formula of the sulfide.

Calcium's atomic number is 20. it forms ions with 18 electrons. what is the electrical charge of a calcium ion?

The doldrums region on Earth is created by an amount of heating from the Sun that results in the rising of warm, moist air, low air pressure, cloudiness, high humidity, and numerous forms of severe weather, such as thunderstorms.