Which is true about the total mechanical energy in a closed system?

O

A. It is not conserved.

O

B. It is zero.

O

c. It does not change.

O

D. It is always decreasing.

The table shows the properties of some organic compounds. Compound A: has only carbon and hydrogen atoms.

Which of the following is the change in energy of an atom emitting a photon of wavelength of 4.35 meters? [Planck's constant, h = 6.626 * 10-34 Js, c = 2.998 * 108 meters/second] a) 1.986 * 10-25 joules b) 2.823 * 10-34 joules c) 9.

Why does fossil fuel use in the United States make the U. S. vulnerable to the political wishes of foreign countries? a. The US is a net exporter of fossil fuels. b. Fossil fuels lead to global climate change. c.

After reaching equilibrium, the rate of formation of products is less than the rate of formation of reactants. After reaching equilibrium, the rate of forming products and reactants is the same. Equilibrium is obtained prior to Te.

A student is using a copper strip and a strong chlorine solution in her experiment. Which of these is a chemical property of one of her materials?

The radioactivity due to carbon-14 measured in a piece of a wooden casket from an ancient burial site was found to produce 20 counts per minute from a given sample, whereas the same amount of carbon from a piece of living wood produced 160 counts

How do the amino acids lysine and alanine combine to form a dipeptide?

Does an oxygen atom form two covalent bonds?

In CCl4 is there a certain length that the main atom Carbon is a certain distance from the Chlorine's?

A mechanic repaired 28 cars and 46 trucks last month. He spent 2.5 hours repairing each of these vehicles. Which equation can be used to find h, the total number of hours the mechanic spent repairing these vehicles?