Hypothesis for isotopes and atomic mass

A neutral atom contains 5 neutrons and 4 protons. How many electrons does it contain?

Celine has a bottle that contains 20% of milk and the rest water. The bottle has 1 liter of water. Write an equation in one variable that can be used to find the total number of liters of milk and water in the bottle.

What might be a long term benefit for the nation from space exploration. A. Taxes will be slower. B. More people will be interested in studying science. C. More science fiction movies will be made. D. More people will become famous

A solution of NaCl (aq) is added slowly to a solution of lead nitrate, Pb (NO 3) 2 (aq), until no further precipitation occurs. The precipitate is collected by filtration, dried, and weighed. A total of 12.11 g CaCl2 (s) is obtained from 200.

Which of the following is balanced chemical equations for the synthesis of NaBr from Na and Br2

Epsom salts (magnesium sulfate) have a solubility of 26.2 grams. If you dissolved 26.0 grams of Epsom salts in 100 g of water at 20 degrees Celsius, what type of solution would this be?

An airplane model is an example of what type of model

A radioactive isotope has a half-life of 2.5 years. Which fraction of the original mass remains unchanged after 10 years?

The air exhaled from the lungs of a smoker has a concentration of 24 ppm CO. Express the concentration as a percent.

The age of fossils can sometimes be determined by radiometric dating, which is based on the constant rate of decay of radioactive isotopes. the time required for half of a radioactive isotope to decay is called the half-life of that isotope.