Which of the following is unique for any given element? a. the number of neutrons b. the charge on the electrons c. the number of protons d. the mass of a neutron

A 500-kg elevator is raised to a height of 10 min 10 seconds. Calculate the power of the motor. 490,000 W 49,000 W 4900 W 490 W

Identify the more stable isotope in each pair.

What is an asteroid?

Is heat, gas production, and color change can all be evidence of chemical change

List the 4 major groups of inorganic chemicals common in cells:

An aqueous solution at 25 °C has a pOH of 12.42. Calculate the pH. Round your answer to 2 decimal places

A student records the mass of a piece of iron. The iron is then left outside until it rusts. What type of reaction occurs, and how does the mass of the object after rusting compare with its original mass?

Which one is a true statement about endothermic reactions? A. Energy from an outside source is continuously being added. B. More heat is given off than is put into the reaction. C. The reactants have less heat energy than the last products. D.

How is the partial pressure of a gas in a mixture calculated?

Part II. Formulas From Names Write the chemical formula of the covalent compounds below. 11. Carbon dioxide CO2