Increasing the concentration increases the speed of reaction by  a) lowering activation energy
b) inncreasing collisions
c) speeding up the reactants
d) exposing more reactant​

How has the scientific community addressed the safety of chemicals? a. chemicals are repeatedly tested, even those that have existed for a long time. b. existing chemicals are tested if they have never been tested before. c. chemicals are tested if they are suspected to have caused a problem. d. only new chemicals are tested.

The mass of a neutron is equal to the mass of a proton plus the mass of an electron. true or false false true

Name the element in group 17, period 2. (periodic table)