Which of the following is not a simple machine

A pulley

B Elevator

C screw

D wheel and axle

The half-life of a material increases with the amount of material present. a. True b. False

Which element has three unpaired electrons in its p orbital?

In a system for separating gases a tank containing a mixture of hydrogen and carbon dioxide is connected to a much larger tank where the pressure is kept very low.

A sample of the radioisotope potassium-40 is crushed to increase its surface area. The temperature of the sample is then lowered 25°C. What affect do these changes have on the rate of nuclear decay? A.) The decay rate doubles B.

What is bond length?

Which list includes three types of chemical formulas for organic compounds? 1. covalent, metallic, isotopic 2. covalent, metallic, molecular 3. empirical, structural, isotopic 4. empirical, structural, molecular

The thermite reaction, in which powdered aluminum reacts with iron oxide, is highly exothermic: 2al (s) + fe2o3 (s) →al2o3 (s) + 2fe (s) use standard enthalpies of formation to find δh∘rxn for the thermite reaction.

According to collision theory, which condition (s must be met in order for molecules to react?

A solution of bleach has about 1.5 g of NaOCl dissolved in 220 mL of solution. What is the molarity?

Enthalpy is a form of?