Writing Chemical Formulae

Q.

What does the formula of a substance tell you?

Q.

The ionic compound formed by the ions ${\text{Fe}}^{3+}$ and $({\text{SO}}_4{)}^{2-}$ has the chemical formula ________.

1. ${Fe}_{2}S{O}_4$

2. ${Fe}_3(S{O}_4{)}_2$

3. ${Fe}_2(S{O}_4{)}_3$

4. ${Fe}_{3}S{O}_4$

Q.

What is meant by a chemical formula?

Q.

What does a chemical formula represent?

1. Number of atoms of each element present in one molecule of the compound.

2. It represents a mole of an atom.

3. Represents bonding between atoms.

4. Represents the number of electrons shared.

Q.

Write the Chemical formula of Arsenic sulphide.

Q.

An element X has valency 3 and an element Y has valency 2 . write the formula of the compound between X and Y

Q.

What is the formula for Calcium Carbonate?

Q.

The molecular formula of potassium nitrate is:

1. $\mathrm{KNO}$

2. ${\mathrm{KNO}}_3$

3. ${\mathrm{KNO}}_2$

4. $\mathrm{KON}$

Q.

What is the information given the chemical formula ${\mathrm{MgCl}}_2$?

Q.

An element has a valency of +3.

What will be the formula of its chloride?

Q.

In the formula $CaB{r}_2$​ what does Ca stand for and what is its valency?

1. Calcium +1

2. calcium -1

3. Calcium +2

4. Calcium -2

Q.

What is a chemical symbol? Write the chemical symbols of the following elements: nitrogen, calcium, boron, gold, and argon

Q.

What is meant by the term chemical formula?

Q.

Choose the elements with their correct symbols.

1. Aluminium - Al

2. Zinc - ZN

3. Fluorine - f

4. Boron - B

Q.

Name the elements represented by the following symbols: $\mathrm{Ag}$, $\mathrm{Au}$, $\mathrm{Sn}$, $\mathrm{Pb}$ and $\mathrm{Hg}$?

Q. The formula of the compound formed by the combination of $C{r}^{3+}$ and $F^{-}$ ions is

1. CrF
2. Cr${}_3$F
3. CrF${}_3$
4. Cr${}_3$F${}_3$

Q. The formula of the compound formed by the combination of $C{r}^{3+}$ and $F^{-}$ ions is

1. Cr${}_3$F
2. CrF
3. Cr${}_3$F${}_3$
4. CrF${}_3$

Q.

Solve the below for $\mathrm{Al}\mathrm{and}\mathrm{S}$.

1. Identify the valency.
2. Crisscross the valency.
3. Write the formula and name of the compound

Q.

What is a chemical formula?

Q.

Molecular formula of water is _______.

Q. The formula of Lead nitrate is ________

1. $\mathrm{Pb}{\left({\mathrm{NO}}_2\right)}_3$
2. $\mathrm{Pd}{\left({\mathrm{NO}}_3\right)}_2$
3. $\mathrm{Pb}{\left({\mathrm{NO}}_2\right)}_2$
4. $\mathrm{Pb}{\left({\mathrm{NO}}_3\right)}_2$

Q.

What is the charge of Mg in $Mg{Cl}_2$ ?

1. 1+

2. 3+

3. 2+

4. 4+

Q.

Name the elements represented by the following symbols:

Hg, Pb, Au, Ag, Sn.

Q.

The name of the cation is always written before the anion in a chemical formula.

1. True

2. False

Q.

Write the symbols for the element argon.

Q. In the chemical formula of a diatomic ionic compound, the valency of the anion is three, then the valency of the cation would be .

1. six
2. two
3. three

Q.

Statement 1: An atom of valency 2 can combine with 2 other atoms of valency 1.
Statement 2: To write the chemical formula, one must know the valency of the element.

1. Both the statements are true

2. Both the statements are false

3. Only statement 1 is true
4. Only statement 2 is true