49 After decaying for 48 hours, l/16 of the original mass of a radioisotope sample remains unchanged. What is the half-life of this radioisotope?

(1) 3.0 h (3) 12 h (2) 9.6 h (4) 24 h

Based on the experimental results, which solvent provided the second best separation of the analyte? a. 0.5% nacl solution b. vinegar c. 0.2% nacl solution d. all solvents had the same degree of separation e. distilled water f. 70% isopropyl alcohol

Carbon dioxide is one of the main gases in the mixture of gases coming out of the kiln. Give two reasons why.

What is produced on the top of the pool of water by the mutual attraction between water molecules

Which of the following is a chemical change? A. Sulfur and iron filings are mixed together in a beaker at room temperature. B. Sulfur and iron filings are mixed together and the iron is removed with a magnet. C.

How many grams of methane gas (CH4) are in a 15.8-liter sample at 1.2 atmospheres and 27°C? Show all work used to solve this problem

Which of the following radioactive emissions is the least penetrating, aloha particles, beta particles or gamma rays

The three major groups p On the periodic table are the

Which of the following has the greatest mass, in grams? a. 1 atom of lead (Pb) b. 0.5 mol copper (Cu) atoms c. 0.3 mol gold (Au) atoms d. 25 atoms of mercury (Hg)

Which one is not a sedimentery rock a.) sandstone b.) limestone c.) quartz d. (coal

Which group is more reactive than the alkaline earth metals?