The half-life of 222rn is approximately 4 days. a sealed vessel is found to contain 1.5 mg of 222rn. how much radon would have been present 12 days before this measurement was taken?

What does x represent in the formula for the compound xcl4?

What effect does a decrease in temperature have on the overall rate of a chemical reaction? a decrease in temperature decreases . the reaction rate will

The table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 9 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of tthe table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 9 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.