You started with 64 g of a radioactive substance. If you have 4.0 g of that substance left, then how many half-lives have elapsed?

a. 2

b. 3

c. 4

d. 5

Identify each of the following as element, compound, homogenious mixture or heterogenios mixture. a. milk b. iron nail c. glass d. sugar e. bottled spring water f. distilled water g. air h. alloy bicycle frame i. propane j. baking soda

Identify the coefficients of the correct balanced equation for the reaction, CaCl2 + AgNO3 ⟶ AgCl + Ca (NO3) 2. A. 1, 2, 2, 1 B. 1, 3, 3, 1 C. 2, 1, 1, 2 D. 3, 1, 1, 3

How many moles of magnesium chloride (mgcl2) are in 1.31 l of 0.38 m mgcl2?

A solution is prepared by dissolving 0.5636 g oxalic acid (H2C2O4) in enough water to make 100.0 mL of solution. A 10.00-mL aliquot (portion) of this solution is then diluted to a final volume of 250.0 mL.

A simple experiment to demonstrate that NaOH is a stronger alkali than NH3

Explain the iodine clock reaction.

1 75 ml of lemon juice are added to 50 ml of water. What is the percent by vo of the solute?

How many moles of tungsten atoms are in 4.8 x 1025 atoms of tungsten?

At what speeds do you criuse down the track of a roller coaster

A sample of hydrogen gas is mixed with water vapor. The mixture has a total pressure of 755 torr and the water vapor has a partial pressure of 24 torr. What amount (in moles) of hydrogen gas is contained in 1.55 L of this mixture at 298 K?