The isotope sodium 20 has how many neutrons

What was one important discovery that the Curies made? A material's radioactivity cannot be changed by altering the material physically. A material's radioactivity can be weakened or intensified by changing it chemically.

What dog is most like a wolf?

How fast do you think the air particles in this room are moving compared to a car going 50 mph (about 22m/s) ? Put your answer is in the form, 'a molecule travels ___ as fast as a car"

A 100 g piece of aluminum is heated to 90°C. It is then dropped into water to bring its temperature down to 20°C. The heat transferred to water is 6300 J. What is the specific heat capacity of aluminum?

Determine what product will be produced at the negative electrode for the following reaction: 2KCl (aq) + 2H20 (1) - > H2 (g) + Cl2 (g) + 2KOH (aq) A. K B. Cl2 C. H2 D. KOH

Which principle explains why it is necessary to have safety belts in cars?

Hydrochloric acid is purchased in 12 molar concentrations. If I needed 200 ml of 2.0 molar HCl, how many milliliters of the concentrated solution would I need

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