The answer is C. They lower the activation energy of an elementary step of a reaction
This makes the reaction rate to increase since less energy is required to make a reaction occur.
Answer:
The period 4 alkaline-earth metal has the name Calcium. An isotope of this element having 20 neutrons has a mass number of 40.
Explanation:
Looking at the periodic table 4th row for the alkaline-earth metal, we can find Calcium which has an atomic number of 20 (or protons number, or z). The mass number is given by the sum of protons and neutrons. If the number of protons in this case is 20 and the number of neutrons is also 20, the mass number A = 40.
It's the actual structure of diamond which made the two different. Diamonds have a tetrahedral structure, and as for graphite, it's not structured in that way. The structures of the two is also the reason why diamond is harder than graphite.
The arrows that represent the phase transitions in which heat energy is gained is : (A). 1, 2 and 3
<h3>Meaning of phase transitions</h3>
Phase transitions can be defined as the changing of matter from one form to another due to the addition or gaining of heat or due to the removal or loss of heat.
Phase transitions in matter are majorly between three phases which are: Solid, Liquid and Gas.
In conclusion, The arrows that represent the phase transitions in which heat energy is gained is : (A). 1, 2 and 3
Learn more about Phase transitions: brainly.com/question/11048831
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You should always do A. form a hypothesis before performing an experiment also the other options cannot happen until after an experiment.
