Answer:
A. the atomic number
Explanation:
It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth.
Answer:
Strong acid
Explanation:
An acid is a substance that interacts with water to produce excess hydroxonium ions in an aqueous solution.
Hydroxonium ions are formed as a result of the chemical bonding between the oxygen of water molecules and the protons released by the acid due to its ionisation. This makes aqueous solution of acids conduct electricity.
A strong acid is one that ionizes almost completely. Examples are:
1. Hydrochloric acid
2. Tetraoxosulphate (VI) acid
3. Trioxonitrate (V) acid
4. Hydroiodic acid
5. Hydrobromic acid
There are seven periods with eighteen columns in the periodic table.
Flammable gases are gases that have the tendency to <u>explode (burst into flames)</u> when they come in contact with the <u>appropriate quantities of air, oxygen, or any suitable oxidant.</u>
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Devices that mix air or oxygen with flammable gasses cannot be used unless approved by an <u>authorized or approved personnel.</u>
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- Examples of flammable gases are hydrocarbons such as <u>Propane, Acetylene</u>, e.t.c.
- Flammable gases are dangerous to humans and the environment and if they are not handled properly, can cause severe damages and even death.
- During the preparation and usage of flammable gases, safety precautions should be properly enforced such as the <u>wearing of appropriate safety gear and goggles</u>.
- Devices that mix air or oxygen with flammable gases cannot be used unless approved by an <u>authorized or approved personnel.</u>
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To learn more, visit the link below:
brainly.com/question/3702349
I suspect this question should read "How long does a red blood cell live." A red blood cell lives for between 100 and 120 days. It takes 7 days for a new red blood cell to develop from stem cells. Stem cells are similar to base cells. They can also be seen as a general template from which specialized cells are made. Stem cells can be taken from a newborn baby's umbilical chord or extracted from an adult blood donor's blood.This