Which of these is a single replacement reaction?

A) Ba(NO3)2+NiSO4BaSO4+Ni(NO3)2
B) 2Fe+3Br22FeBr3
C) CaCl2+Na2CO3CaCO3+2NaCl
D) Fe+CuSO4Cu+FeSO4

1 Answer
Jul 15, 2017

(D)

Explanation:

A single-replacement reaction (also called a single-displacement reaction) is one in which a pure element and a compound react chemically so that the products include another pure element and a different compound via exchanging of two species.

In other words, it is where an element reacts with a compound and replaces one component of the compound:

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Let's examine each option:

  • (A)

Option (A) is the reaction

Ba(NO3)2+NiSO4BaSO4+Ni(NO3)2

This is a typical example of a double-replacement reaction (or double-displacement reaction), in which two substances exchange their cations to form two new substances:

http://study.com

Since this is obviously not a single-replacement reaction, we can eliminate (A).

  • (B)

Option (B) is the reaction

2Fe+3Br22FeBr3

This is what's called a synthesis (or combination) reaction, where two reactants combine to form only one product:

image.slidesharecdn.com

This is not a single-replacement reaction, so we can also eliminate (B).

  • (C)

Option (C) is the reaction

CaCl2+Na2CO3CaCO3+2NaCl

This, like answer (A), is a double-replacement reaction, so we eliminate (C).

This leaves us with one final option:

  • (D)

Option (D) is the reaction

Fe+CuSO4Cu+FeSO4

We can see from the color code that this is a single replacement reaction, conforming to the first image above, so option (D) is correct.