The temperature of a sample of water changes from 10°C to 20°C when the sample absorbs 418 joules of heat. What is the mass of the sample?

(1) 1 g (3) 100 g

(2) 10 g (4) 1000

Why does the addition of acid increase the solubility of calcium phosphate? a. It decreases the phosphate ion concentration, forcing the equilibrium to the right. b. It increases the phosphate ion concentration, forcing equilibrium to the left. c.

Are all metals acidic in nature and all non-metals basic? and what is the nature of their oxides?

What happens to atoms after a chemical change?

If a 1.45 M solution has 2.43 g HCl dissolved, what is the volume of solution? (Change g HCl into mol using molar mass)

What is the total number of electrons shared in a double covalent bond? (1) 1 (3) 3 (2) 2 (4) 4

In a titration 25.0 ml of a. 20 M NaOH solution is used to neutralize 10.0 ml of HCl. Write the equation for this neutralization reaction and calculate the molarity of the acid.

4*C: 4cm 8*C: 10cm 12*C: 14cm 16*C: 18cm 20*C:24cm 24*C: 12cm what is the independent variable, dependent variable and three constant variables?

In the chemical laboratory, why do scientists use a mortar and pestle? a. to increase surface area of a solute b. to decrease surface area of a solute c. to increase temperature of a solute d. to decrease temperature of a solute

Is a mixture being separated into two elements a chemical change

Which electrons are lost by an atom of iron when it forms the Fe3 + ion? A. One s orbital electron and two d orbital electrons B. Two s orbital electrons and one d orbital electron C. Three s orbital electrons D. Three d orbital electrons