Of the following, which does not signify a chemical reaction?

1) tarnish

2) release of heat

3) changing state

4) release of gas

Which of the following instruments is used to measure air pressure? A. Thermometer B. Barometer C. Hygrometer D. Anemometer

Calculate the number of carbon atoms in 5.6 liter of acetylene

How many ions form when 39 grams of calcium fluoride are added to excess water? a. 0.50 mol b. 1.0 mol c. 1.5 mol d. 3.0 mol

Why is it hard to prove the law when a gas is produced?

Organisms can pass on genetic information through asexual or sexualreproduction. Which if the following statements best describes how asexual reproduction differs sexual reproduction

Why electrons are transferred during the course of the reaction between magnesium and oxygen?

Human muscle stores sugars in the form of

How much heat is needed to raise the temperature of 75 g of a substance by 15 C when the specific heat is 0.92 J/g-C?

A nitric acid solution flows at a constant rate of 5L/min into a large tank that initially held 200L of a 0.5% nitric acid solution. The solution inside the tank is kept well stirred and flows out of the tank at a rate of 10L/min.

How many molecules are in 237g (about a cup of water)