If a neutral atom of beryllium has 4 protons and 5 neutrons, what is the mass number of the atom?

Relative humidity changes with temperature true or false?

Which does not affect the rate of pulmonary and systemic gas exchange? a. partial pressure of the gases. b. surface area available for gas exchange. c. diffusion distance. d. number of gases to be exchanged. e.

Why was Becquerel's experiment a first step in discovering radioactivity? A. It showed that a substance could phosphoresce when it was not exposed to light. B. It showed that the substance that was used by Becquerel could phosphoresce. C.

What mass of benzoic acid would you dissolve in 350.0 mL of water to produce a solution with a pH = 2.85?

How many protons, neutrons, and electrons are in 195Pt2+?

A fog over a lake. what two changes of state must occur to produce the fog? do the water molecules absorb or release energy during these changes of state? what happens to the motion of the water molecules as a result?

Limes have a [H3O+] of 1.3 x 10-2 mol/L. Their pOH is

The human body is 0.0040% iron. How many milligrams of iron does a 165 pound person contain?

Which of the following is the correct Lewis structure for ammonia (NH3) ? Note: Hydrogen and nitrogen have one and five valence electrons respectively.

Which of the following statements is true? A. Particles of a solid have a very orderly, three dimensional arrangement and do not move B. Particles of a liquid change shape and volume C.