Answer:
Chemical formula.
Explanation:
A chemical formula have fix proportion of atoms of elements.
Chemical formula:
A chemical formula is the way of presenting the chemical proportion of atoms of those elements, that combine to form a compound.
For example:
Water consist of two atom of hydrogen and one atom of oxygen. The atoms of both elements combine to form a compound i.e water. The atoms of both elements always combine in a fixed ratio which is 2:1 in molecule of water.
H₂O
2:1
Carbon dioxide consist of two atom of oxygen and one atom of carbon. The atoms of both elements combine to form a compound i.e carbon dioxide. The atoms of both elements always combine in a fixed ratio which is 1:2 in molecule of carbon dioxide .
CO₂
1;2

What is the difference between a quantity and a unit?
Answer:
Physical quantities are a characteristic or property of an object that can be measured or calculated from other measurements. Units are standards for expressing and comparing the measurement of physical quantities. All units can be expressed as combinations of four fundamental units.
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Answer:
Actually, The Henderson - Hasselbalch equation allows you to calculate the pH of the buffer by using the pKa of the weak acid and the ratio that exists between the concentrations of the weak cid and conjugate base. The pKa of formic acid is equal to 3.75. In this case, the pH of the solution will be equal to the acid's pKa .
Answer: Total number of Protons PLUS Neutrons
Explanation:
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