The half-life of a radioactive isotope is 20.0 minutes. What is the total amount of a 1.00-gram sample of this sample of this isotope remaining after 1.00 hour?

Which is the most polar bond? a. H-Se b. P-Br c. N-I d. No right answer.

When 15.6 g of fluorite (caf2) reacts with excess sulfuric acid, hydrogen fluoride gas is collected at 709 torr and 25.5°c. solid calcium sulfate is the other product. what gas temperature is required to store the gas in an 7.

2H2 + O2à2H2O How many water molecules are created when 32 grams of oxygen react completely with 4 grams of hydrogen? A. 2 B. 20 C. 6.02 * 1023 D. 1.2 * 1024

Determine the enthalpy of neutralization in Joules/mmol for a solution resulting from 19 mL of 0.9 M NaOH solution and 19 mL of a HCl with the same molarity. If separately, each had a temperature of 28.

If a leaf falls from a tree we assume that it is in free fall and not affected by air resistance, how many force vectors does the leaf have?

What organelle does the process of cellular respiration?

How much heat is absorbed during production of 127 g of NO by the combination of nitrogen and oxygen? N2 (g) + O2 (g) →2NO (g), ΔH = + 43 kcal/mol

Which of the following is the result of the process that binds many amino acids on to another? a. protein b. allele c. dna d. rna

What does the electron transport chain do to the concentration of hydrogen ions (protons) ?

What is the cation name for alcl3?