Element X has five valence electrons, element Y has one valence electron, and element Z has five valence electrons. Which two of these elements are most likely to have similar properties? Explain your answer

What happens as you increase the temperature of a reaction? A) More collisions occur and the time required for the reaction increases. B) Fewer collisions occur and the time required for the reaction decreases.

Given STP conditions, how many milliliters of hydrogen gas are produced by the reaction 0.020 mol of magnesium with excess of hydrochloric acid?

Which of the following is a type of electromagnetic radiation? a. Electrons b. Neutrons C. Electromagnetic waves d. Helium nuclei

What is Delta. S for the reaction N2 (g) + O2 (g) Right arrow. 2NO? Use Delta. G = 173.3 kJ at 303.0 K and Delta. H = 180.7 kJ. Use Delta. G = Delta. H - TDelta. S. 7.4 J/K 7.4 kJ/K 24.42 kJ/K 24.42 J/K

Trees obtain carbon from a decaying organisms b. sunlight c. the atmosphere d. none of the above

When 4.70 g of a nonelectrolyte solute is dissolved in water to make 935 mL of solution at 28 °C, the solution exerts an osmotic pressure of 943 torr.

What is the half-life of a radioisotope if a 40 g sample becomes 10 g after 20 minutes?

What fact shows that baking a chocolate chip cookie is a chemical reaction? The final product tastes and looks different from the original ingredients. All of the ingredients are mixed up in the cookie.

What specifically does STR measure? A) STR length B) the number of repeating units C) distance traveled on electrophoresis gel D) the difference between the number of repeating units between two STRs

The reaction A (g) ⇌ 2 B (g) A (g) ⇌ 2 B (g) has an equilibrium constant of K = 0.010 K = 0.010. What is the equilibrium constant for the reaction B (g) ⇌ 1 2 A (g) ?