In potassium-argon dating, how does the proportion of remaining potassium in a rock or fossil change over time?

How many ions form when 39 grams of calcium fluoride are added to excess water? a. 0.50 mol b. 1.0 mol c. 1.5 mol d. 3.0 mol

Instruction Active Identifying Direction of Heat Flow Scenario Object 1 Object 2 Indicate the direction of heat flow in each scenario.

How many electrons are in the highest energy level of sulfur? A. 2 B. 8 C. 6 D. 4

List the number of each type of atom on the left side of the equation 2Na3PO4 (aq) + 2CoCl2 (aq) →2Co3 (PO4) 2 (s) + 6NaCl (aq) Enter your answers separated by commas (the order of the numbers is the same as the order of the elements on the left

A 0.105 L sample of an unknown HNO 3 solution required 45.5 mL of 0.150 M Ba (OH) 2 for complete neutralization. What is the concentration of the HNO 3 solution?

A balloon is filled with 12L of air at a pressure of 2 atm. What is the volume of ballon if the pressure is changed to 3 atm?

What ionic bond occurs between what particles? A. Two Negative Ions B. A positive and negative ion C. Two positive ions D. Two neutral atoms

Which of the following are good traits of a hypothesis? it will be able to be tested it can predict an outcome it will explain the observations all of these

What is the mass of a box of nails

In a phase change of water between the liquid and the gas phases, 770.1 kJ of energy was released by the system. What was the product, and how much of it was formed in the phase change? (dа ta: H₂O (l) → H₂O (g) ΔH = 44.01 kJ/mol.) A.