Which of the following methods will usually cause a reaction to speed up? Group of answer choices

Removing the catalyst.

Combining the reactants at a lower temperature.

Grinding one of the reactants into a powder.

Reducing the concentration of reactants.

Asingle atom of an element has 21 neutrons, 20 electrons, and 20 protons. which element is it? ok o z

Determine the reaction and balance the following equations urgent due in the morning

What energy conversion occurs when a sling shot is used to shoot a rock across the room? (2 points) question 2 options: 1) stored mechanical energy is converted to mechanical energy. 2) stored mechanical energy is converted to radiant energy. 3) gravitational energy is converted to radiant energy. 4) gravitational energy is converted to mechanical energy.