It can be a compound or a single element. An element is a pure substance that cannot be separated into simpler substances by chemical or physical means. There are about 117 elements, butcarbon, hydrogen, nitrogen and oxygen are only a few that make up the largest portion of Earth.
I would say d.
Answer:
b. 7.5 x 10^-3
Explanation:
To solve this problem we need to keep in mind the <em>definition of molarity</em>:
- Molarity = moles of solute / liters of solution
With the above information in mind it is possible to calculate the moles of solute, given the volume (10 mL) and concentration (0.75 M) of the solution:
- First we<u> convert 10 mL to L</u> ⇒ 10 mL / 1000 = 0.01 L
Then we <u>calculate the moles of AgNO₃</u>:
- moles of solute = Molarity * Liters of solution
- 0.01 L * 0.75 M = 7.5x10⁻³ mol AgNO₃
<em>One mole of AgNO₃ contains one mole of Ag⁺</em>, thus the number of Ag⁺ moles is also 7.5x10⁻³.
Answer:
is used to break reactant bonds and/or make new product bonds.
Explanation:
<em>The correct answer would be that </em><em>activation energy is used to break reactant bonds and/or make new product bonds</em><em>.</em>
The <u>activation energy is the minimum energy that must be overcome by the reactants in a reaction in other to become products</u>. In order for products to be formed, the bonds between reactants must be broken and new ones must be formed to arrive at the products. In other words, the activation energy can be seen as the energy required to break the bonds between reactants and form the bonds between products during the course of a reaction.
<em>Activation energy is required even in the presence of enzymes. The latter only catalyzes reactions by lowering the minimum energy required to break the bonds between reactants and form new ones between products</em>.
