Actinium-226 has a half-life of 29 hours if 100 mg of actinium-226 disintegrates over a period of 58 hours how many mg of actinium-226 will remain

What are the horizontal rows of the periodic table called

Rank the temperatures from the highest to the lowest. 133F 351K 25C 273K 146C 58F 95F

Calcium atoms have two electrons in the outermost shell. As a result, you would expect calcium to form ions with a charge of A) + 1. B) + 2. C) - 1. D) - 2. E) 0.

At a certain temperature the vapor pressure of pure acetyl bromide (CH_3 COBr) is measured to be 0.75 atm. Suppose a solution is prepared by mixing 51.8 g of acetyl bromide and 123. g of thiophene (C_4H_4S).

In which region of the periodic table do the elements NOT normally react chemically with other elements? A) Metals B) Metalloids C) Non-metals D) Noble Gases

Rank the temperatures from the highest to the lowest. 133F 351K 25C 273K 146C 58F 95F

Calculate the density of sulfuric acid if 35.4 mL of the acid weighs 65.14 g.

Where the single machos?

A reaction will be spontaneous only at low temperatures if both ΔH and ΔS are negative. For a reaction in which ΔH = - 320.1 kJ/mol and ΔS = - 86.00 J/K · mol. Determine the temperature (in °C) below which the reaction is spontaneous.

Is it possible for a balloon with an initial internal pressure equal to 250.0 kPa to naturally expand to four times its initial volume when the temperature remains constant and the atmospheric pressure is 101.3 kPa?