1. Fluorine-21 has a half-life of approximately 5 seconds. How much of a 200 gram sample would remain after 1 minute.

The level of electromagnetic radiation is much higher is space. True False

For hydrocyanic acid, HCN, Ka = 4.9 * 10-10. Calculate the pH of 0.20 M NaCN. What is the concentration of HCN in the solution? for the ph i got 10 is that right?

Suppose you put 50 ml of water in the can instead of 100 ml and heated it to 40 degrees instead of 20 degrees. in what ways if any would this affect the results of the investigation

Why are chemical reactions often carried out using solutions? The heterogenous nature of solutions prevents the reactants from freely mixing. The amount of each reactant can be controlled by adjusting the volume of each solution that is used.

Which element, represented by X, reacts with fluorine to produce the compound XF2? (1) aluminum (3) magnesium (2) argon (4) sodium

How are revolution and year related

Read the scientific question below. "Does sunlight make plants live?" What is a likely hypothesis for the question?

A chemist is using a solution of HNO3 that has a pH of 3.75. What is [H+] for the solution?

What is the oxidation number for CO2

Which is a property of acids in aqueous solutions?