Chemical reactions are basically divided into two major classes depending on whether the reaction lose energy or gain energy from the environment during the course of the reaction. The two classes of reaction are exothermic and endothermic reaction.
An exothermic reaction is a type of reaction in which the reaction system lose energy to the environment and thus, the energy content of the reactants is more than that of the product formed. Because of this, the enthapyl change of an exothermic reaction is always negative.
An endothermic reaction is a type of reaction in which the reaction system absorb energy from the environment. Thus, the energy contents of the products is always higher than that of the reactants and the enthapyl change of the reaction is always positive. During the course of the reaction, the reaction container is usually cold to the touch because energy is been absorbed from the environment.
Explanation:
Scientifically speaking, metals are naturally occurring chemical elements that are typically hard, lustrous, and good conductors of both heat and electricity. Examples include iron, gold, silver, copper, zinc, nickel, etc., but also elements we don't normally think of as metals.
Answer : The volume of stock solution needed are, 12.5 mL
Explanation :
Formula used :

where,
are the initial molarity and volume of copper (II) chloride.
are the final molarity and volume of stock solution of copper (II) chloride.
We are given:

Putting values in above equation, we get:

Hence, the volume of stock solution needed are, 12.5 mL
Answer:
Here's what I get
Explanation:
At the introductory level of chemistry, I can think of only two situations when you use Greek prefixes.
They indicate the number of atoms or groups in a molecule when you are naming a compound.
1. Binary covalent compounds
For example, P₂S₅ is diphosphorus pentasulfide.
2. Hydrates
For example, Na₂SO₄·10H₂O is sodium sulfate decahydrate.
Answer:
Examples of Solids
1. Brick
2. coin
3. Iron bar
4. rock
5. wood
Examples of Liquids
1. Blood
2. Honey
3. Wine
4. Water
5. oil
Examples of Gases
A gas does not have a defined shape or volume, so it can expand to fill any size or shape of a container. Particles in gases are widely separated, compared to those in liquids and solids.
Explanation: