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2 years ago

Round off each of the following numbers to two significant figures:

Chemistry

2 answers:

Kay [80]2 years ago

7 0

A) 5.2 x 10^2
B) 86.
C) 6.4 x 10^3
D) 5.0
E) 22.
F) 0.89

strojnjashka [21]2 years ago

7 0

Answer:

(a) 5.1 × 10²

(b) 86

(d) 5.0

(e) 22

(f) 0.89

Explanation:

To round off a number, we consider the number that is to its right. If that number is 5 or higher, we increase the number of interest. If the number to the right is 4 or lower, the number of interest remains the same. When taking less significant figures, we might need to use scientific notation for large or small numbers.

Round off each of the following numbers to two significant figures:

(a) 517 → 5.1 × 10²

(b) 86.3 → 86

(c) 6.382 × 10³ → 6.4 × 10³

(d) 5.0008 → 5.0

(e) 22.497 → 22

(f) 0.885 → 0.89

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Answer:

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Explanation:

In this exercise you have find the enthalpy of reaction this is the difference between enthalpy of reactans and products,

For the following equation

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Answer: $-3.8\times 10^{5}J$

Explanation:

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$E^0=E^0_{cathode}- E^0_{anode}$

Where both $E^0$ are standard reduction potentials.

$E^0_{[Mn^{2+}/Mn]}= -1.18V$

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$\Delta G^0=-nFE^0$

$\Delta G^0$ = gibbs free energy

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