Which two elements have the same number of valence electrons?

A.) Na and Sr

B.) Zr and H

C.) O and S

D.) Mg and P

Suppose you need to make the following two precipitates (by two different precipitation reactions) : MgCO3 and Ca3 (PO4) 2.

Which statement describes thylakoids? Glucose is formed here. Water molecules are formed here. Only photosystem II functions here. Photosystems I and II function here.

A solution of 34% nacl is separated by a semipermeable membrane to a solution of 22% glucose. the membrane is only permeable to water. which direction will the net osmosis occur?

Which of the following compounds is an Arrhenius base? Which of the following compounds is an Arrhenius base? A.) CH3OH B.) HOCl C.) CH3CO2H D.) SrOH

The Kp of calcium iodate is 7.1 x 107 What is the concentration of Ca2 + in equilibrium with Ca 3.3 x 10-2 M? 2.3.3 * 10M b. 8.1 x 10 SM c. 2.2 * 10-SM d. 6.5 x 10 M e. 7.1 x 10-3 M

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.

How does hess's law use intermediate reactions to calculate the enthalpy of a desired reaction?

Which atomic particle dtermines the chemical behaviour of an atom?

If you could travel to the Sun and back, about how far would you travel? A. 1 AU B. 2 AU C. 5 AU D. 10 AU

A scientist is conducting a descriptive experiment where she is monitoring sea level along coastal towns in California. What is a major benefit of this experiment? The relationship shows cause and effect. It is repeatable.