How many dots are shown in the electron dot diagram for calcium, in group II and period 4 with 20 protons and 20 electrons? a. four c. eight b. two d. twenty

What do engineers use to test their designs of new technologies? A. polls B. models C. pie charts D. reference materials

The volume of a balloon decreases, what happens to the air pressure within the balloon? Assume all other properties remain constant. A. It stays the same. B. It increases. C. It decreases.

Given: N2 + 3H2 → 2NH3 Bond Bond Energy (kJ/mol) N≡N 942 H-H 432 N-H 386 Use the bond energies to calculate the change in enthalpy for the reaction. The enthalpy change for the reaction is kilojoules.

Nitric acid, a very important industrial chemical, is made by dissolving the gas nitrogen dioxide (NO2) in water. Calculate the moles of gas produced in 2 L volume container, 747 torr and 50 ºC if the gas behaves as ideal:

Which of the following is nicknamed the "powerhouse" of the cell?

How do carbon-12 and carbon-13 differ? Select all that apply. They have different amounts of neutrons. They have different atomic charges. They have different mass numbers. They have different amounts of electrons.

Why arent the jaguars and sloths growing and thriving?

If a spoon is hot after leaving it on the pot that was on the stove. What heat transfer is that.

If a small amount of ferrous ammonium sulfate is spilled when transferring

List one reason as to why historical growth has slowed in recent years.