1.Write down the expected charges for the following elements: [1-2/Ai/ii] a. P

b. Na

c. Ca​

What element has similar physical and chemical properties as boron.

When a beta particle is emitted, the mass number of the nucleus a. decreases by one b. increases by one c. remains the same d. decreases by two

How does a sample of helium at 15 degree celsius compare to a sample of helium at 215 k? a) the helium at 15 degrees celsius has a higher average kinetic energy that the sample at 215 k. b) the helium at 15 degrees celsius has lower nuclear energy that the sample at 215 k. c) the helium at 15 degrees celsius has slower- moving atoms that the sample at 215 k. d) the helium at 15 degrees celsius has smaller atoms than the sample at 215 k.