C + O2 - -> CO2 + 60kJ

is the reaction exothermic or

endothermic?

Which of the following would form an anion? He H N B

Which two elements are most abundant within the sun?

Identify the oxidizing agent and the reducing agent in the following reactions: (i) 8NH3 (g) + 6NO2 (g) = > 7N2 (g) + 12H2O (l) (ii) Zn (s) + AgNO3 (aq) = > Zn (NO3) 2 (aq) + Ag (s) (unbalanced)

In 1932, james chadwick discovered a new subatomic particle when he bombarded beryllium-9 with alpha particles. one of the products was carbon-12. what particle did chadwick discover?

Which one has the largest atomic mass: K, Ca, or Sc

Which of these is a chemical property? A. Mercury is a dense liquid. B. Iodine vapor has a purple color. C. Aluminum is a very conductive metal. D. Ice melts at 0°C. E. Iron rusts in wet weather.

Which of the following is not true about the importance of the carbon cycle to living things? a. Plants use carbon dioxide to make energy. b. Carbon is the second most abundant molecule in organisms. c.

Fruit flies can either have a brown body or a black body. The allele for a brown body (B) is dominant to the allele for a black body (b). A brown fruit fly was crossed with a black fruit fly as shown below.

A light-year measures the distance a light beam can travel in one year. One light-year is equal to 9 500 000 000 000 kilometers.

The first ionization energy, e, of a potassium atom is 0.696 aj. what is the wavelength of light, in nm, that is just sufficient to ionize a potassium atom? values for constants can be found here.