Which is true about the total mechanical energy in a closed system?

O

A. It is not conserved.

O

B. It is zero.

O

c. It does not change.

O

D. It is always decreasing.

The atomic number of the sodium atom is 11. The atomic mass number can be estimated by rounding the atomic mass to 23.

An s sublevel is represented by the quantum number

How do you identify a mineral there are six things

Which of the following is a homogeneous mixture? a. sodium chloride b. oxygen c. salad d. salt water

How does acid taste and feel?

The first-order decomposition of n2o at 1000 k has a rate constant of 0.76 s-1. if the initial concentration of n2o is 10.9 m, what is the concentration of n2o after 9.6 s

When a catalyst lowers the activation energy of a reaction the rate of the reaction?

Liquids: A) must be contained to stay in one spot B) have a variable volume, but a fixed mass C) are usually more dense than solids and gases D) cannot be changed into gases

Given the following list from the activity series of metals (from most active to least active) K, Na, Al, Mn, Cr, Cd, Co, Pb, Hg which reaction would you NOT expect to occur? 1. Co²⁺ (aq) + Al (s) → Al³⁺ (aq) + Co (s) 2.

Chemical reactions that release energy A. will not occur. B. need catalysts to occur. C. will always explode. D. often occur spontaneously.