Which of the following represents a chemical change?

A. Bending a wire

B. Freezing of water

C. Fireworks exploding

D. Melting of a wax candle

Choose the situation this is an example of heat transfer by radiation A.) An ice cube melts while you hold it in your hand. B.

How potential energy changes when you pull a magnet off a refrigerator door

According to the expansion law galaxies expand away from each other equally? Explain.

How did Dalton gather evidence for the existence of atoms? A. by observing an element's atomic structure through a microscope B. by calculating the number of subatomic particles in an element C.

A mixture of 50% benzene and 50% toluene is contained in a cylinder at 39.36 in. hg absolute. calculate the temperature range in which a two phase system can exist.

An insulator: A. Conducts heat well B. Does not conduct heat well C. Is used to heat cold objects D. Is used to cool hot objects

Which of the following choices would have a negative entropy change? A. N2 (g) + 3H2 (g) - >2NH3 (g) B. CaCO3 (s) - > CaO (s) + CO2 (g) C. H2O (s) - > H2O (l) D. Fe2O3 (s) + 3C (s) - > 2Fe (s) + 300 (g)

Increasing the temperature of a liquid-solid solution will:

What is the most abundant substance dissolved in sea water? magnesium chloride sodium chloride

Problem 5.32 - enhanced - with feedback the rolling resistance for steel on steel is quite low; the coefficient of rolling friction is typically μr=0.002. suppose a 180,000 kg locomotive is rolling at 22 m/s on level rails.