Variable Valency

Q.

Define valency by taking examples of silicon and oxygen.

Q.

Define valency. Give valency to copper and iron?

Q. _{If valency of silver is +2 and valency of nitrate is -1, then when they both reacts they form} AgNO3​​​​.Explain why?
​​

Q.

Define the valency of an element. Calculate the valency of nitrogen in ${\mathrm{N}}_2{\mathrm{O}}_5$

Q.

The radical 'cuprous' has a valency of?

1. 1

2. 2

3. 3

4. 4

Q.

What do you mean by variable valency ?

Q.

Which of the following element shows variable valency?

1. Carbon

2. Chlorine

3. Nitrogen

4. Argon

Q.

Why do transition metals exhibit variable valencies?

Q.

An element ‘X’ has six electrons in its outer or valence shell.

Its valency is___________(+2, -2, -1)

Q.

5. Write the names of the following compounds:

i. FeCl₂

Q.

The valency of sodium is _____.

​​

1. 3

2. 4

3. 1

4. 2

Q. How to calculate valency factor

Q.

What is variable valency ? Name two elements having variable valency and state their valencies.

Q.

Which of these is/are valency/valencies of iron?

1. 1

2. 2

3. 3

4. 4

Q. Give reasons why copper exhibits variable valency.

Q. What is the variable valency? Give three examples of elements having variable valency.

Q. Which of the following elements shows variable valency?

1. $Mg$
2. $Na$
3. $Zn$
4. $Fe$

Q. How many valence electrons are present in Q?

1. 4
2. 5
3. 6
4. 7

Q. Commercial sample of $H_2{O}_2$ is labeled as 10 V. Its % strength is nearly

1. 3
2. 6
3. 9
4. 12

Q. Phosphorus has five valence electrons in its valence shell.

1. True
2. False

Q. Both transition as well as non-transition elements show variable valencies. Explain.

Q. 1 g of a metal, having no variable valency, produces 1.67 g of its oxide when heated in air. Its carbonate contains 28.57% of the metal. How much oxide will be obtained by heating 1 g of the carbonate ?

1. 0.4771
2. 0.54
3. 0.64
4. 0.5321

Q.

Name three trivalent anions with their formulae and valencies.

Q.

A scientist while working on an experiment found a new compound X.

He represented the compound X as $Fe(HC{O}_3{)}_3$.What is the valency of Fe(Iron)?

1. 16
2. 6
3. 8
4. 15

Q. Which of the following exhibits variable valency?

1. $Na$
2. $Al$
3. $K$
4. $S$

Q. What is valency?

Q. Which of the following radicals are bivalent?

1. Hydrogen phosphate
2. Sulphate
3. Perchlorate
4. Nitride

Q.

Number of valence electrons in ${\mathrm{Na}}_{}^{+}$ion are :

1. 11

2. 10

3. 8

4. Zero

Q.

Write the name of two elements, which show variable valency.

Q. Assertion :Transition metals show variable valence. Reason: Due to a large energy difference between the $n{s}^2$ and $(n-1)d$ electrons.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect