Which of the following consists of positive and negative ions bound together and held in place in a crystalline solid?

A. Covalent bonds

B. Ionic compounds

C. Molecular compounds

D. Molecules

What is the number of CO2 molecules in 0.0180 mol of CO2

What was the advantageous adaptation mentioned that humans have evolved in order to survive

A mixture containing particles that will settle out if left undisturbed is called a a. colloid c. suspension b. colligative d. electrolyte

Classify each of the following changes as Physical or Chemical: (a) Coal burning (b) ice melting (c) mixing chocolate syrup with milk (d) explosion of a firecraker (e) magnetizing of a screwdriver

Does a liquid release energy or absorb energy when it changes into a gas? into a solid?

Which of the following represents a chemical change? Bending a wire Freezing of water Fireworks exploding Melting of a wax candle

5.00 L of a gas is collected at 100K and then allowed to expand to 20.0 L. What must the new temperature be in order to maintain the same pressure? A. 400 °C B. 127 °C C. 223 °C D. 627°C

Before the initial explosion was the matter hot or cold

Which of the following atoms has seven valence electrons? chlorine (Cl) nitrogen (N) manganese (Mn) oxygen (O)

A.) During an experiment, a student adds 2.90 g of CaO to 400.0 mL of 1.500 M HCl. The student observes a temperature increase of 6.00 °C. Assuming the solution/'s final volume is 400.0 mL, the density if 1.00 g/mL, and the heat capacity is 4.