Answer: The correct statement is (A new substance is formed and the process can usually NOT be undone.)
Explanation:
A chemical reaction is simply defined as the reaction between two or more elements in which a new substance is formed and the process can usually not be undone. Different types of chemical reaction includes:
-- combination reaction: this occurs when two or more reactants form a product. For example: In the burning of coal, It combines with oxygen to produce carbon dioxide. Also in the burning of wood, carbon dioxide is given off and ashes are formed. Because new substance is being formed, they often can't be undone. The ashes formed can't be changed back into wood. Other types of chemical reaction are listed below.
-- Decomposition reaction
-- Single displacement reaction
-- Double displacement reaction
-- combustion reaction
-- Redox reaction
For the product of a chemical reaction to be undone (reversed), it has to undergo another chemical process different from the one that produced it.
Answer:
The pressure in the gas is 656mmHg
Explanation:
In calculating the pressure of the gas;
step 1: convert the height of the mercury arm to mmHg
9.60cm = 96.0 mmHg
step 2: convert 752 torr to mmHg
I torr is 1 mmHg
752 torr = 752mmHg
Step 3: since the level of mercury in the container is higher than the level of mercury exposed to the atmosphere, we substrate the values to obtain our pressure.
So, 752mmHg - 96mmHg = 656mmHg
The pressure in the gas container is therefore 656mmHg.
N. B : if the mercury arm is in lower position, you add.
Answer:
5 electrons
Explanation:
When an atom loses are gain the electrons ions are formed.
There are two types of ions.
Anion
Cation
1 = Anion
It is formed when an atom gain the electrons. when atom gain electron negative charge is created on atom. For example.
X + e⁻ → X⁻
2= Cation
It is formed when an atom loses the electrons. when atom lose electron positive charge is created on atom. For example.
X → X⁺ + e⁻
When an atom loses three electrons +3 charge is created. If this atom have 8 protons it means there were 8 electrons too. When it lost three electrons then remaining number of electrons are 5.
X → X³⁺ + 3e⁻
