Which statement describes friction?

O It is perpendicular to the surfaces that rub together.

O It causes a change in motion.

O It occurs in the same direction as the push force.

O It pulls downward on a moving object.

Which of the following statements is true about catalysts? and Why? a. Catalysts slow down the rate of chemical reactions b. All catalysts are enzymes c. Catalysts are used up during a chemical reaction d.

The mass of the electron is about equal to the neutron. almost the same as the proton. very small compared to the proton. very large compared to the neutron. light 2:21 Tools

What is a measure of force that is generated by the action of gravity on the mass of an object

Calculate the activation energy (ea in kj/mol for a reaction if the rate constant (k is 2.7 * 10-4 (m-1sec-1 at 600 k and 3.5 * 10-3 (m-1sec-1 at 650 k.

How many moles are in 88.1 of magnesium

What is the most metallic element

What must be true for a substance to be able to dissolve in water? a) the solute particles must have a strong attraction for the water particles b) the solute must be able to react with water at the given temperature c) there must be enough energy

Drag the appropriate elements to their respective bins

Compare how an increase in wavelength affects sounds and light waves.

The addition of an acid to water increases the [H30*) of the solution and increases the solution pH. True or False True False