Will give brainliest!

What percentage of a substance remains after 7 half-lives have passed?

2.5

1.25

0.78

0.39

The following is an example of which type of chemical reaction? Na (s) + H2O (l) Imported Asset NaOH (aq) + H2 (g) Single replacement Decomposition Double replacement Combustion

According to the second law of thermodynamics, energy tends to become more spread out. True False

Which of the following is a chemical change? A. a solution of salt water being diluted as water is added to it B. soil drying as water evaporates C. a rock eroding as the wind removes particles from it D.

37.0 °C = °F (human body normal temperature)

How are metallic bonds different from ionic and covalent bonds?

Does The human brain retains more information than all the books in the Library of Congress

Will an object with a density of 0.97 g/ml float or sink in water

Which subatomic particle contributes least to the mass of the atom? which subatomic particle contributes least to the mass of the atom? neutron electron proton all of these contribute equally?

2H2S (g) 2H2 (g) + S2 (g) Kc = 1.67 * 10 ^-7 at 800 C A 0.500 L reaction vessel initially contains 0.0125 mol of H2S at 800 C. Find the equilibrium concentrations of H2 and S2.

An atom has an atomic number of 9 a mass number of 19 and an electron configuration of 2-6-1 explain why the number of electrons in the second and third shells shows that this is in an excited state