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3 years ago

How many significant figures in 1. 19.99 2. 140486 3. 0.0609 3. 5.08 ?

Chemistry

1 answer:

tangare [24]3 years ago

5 0

1. 4 significant numbers

2. 6 significant numbers

3. 3 significant numbers

4. 3 significant numbers

<h3>Further Explanation </h3>

Significant numbers are numbers obtained from the measurement results of exact numbers and the last number estimated

1. 19.99

all non-zero numbers are significant numbers , so there are 4 significant numbers

2. 140486

a zero which is located between two non-zero numbers including a significant number , so there are 6 significant numbers

3. 0.0609

a zero in front of a decimal point is not a significant number, so there are 3 significant numbers (6,0 and 9)

4. 5.08

Any zeros between two non-zero numbers are significant, so there are 3 significant numbers(5,0 and 8)

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<h3>Further explanation </h3>

The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.

Usually radioactive elements have an unstable atomic nucleus.

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$\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}$

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3 years ago

Calculate the molarity of a solution containing 5.6 mol of sodium hydroxide dissolved in 2.1 L of water

yKpoI14uk [10]

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3 years ago

A saline solution contains 1.6 % NaCl by mass.How much NaCl is present in 57.2 g of this solution?

nekit [7.7K]

Answer:

0.92 g

Explanation:

Given data:

Percentage of NaCl = 1.6%

Amount of NaCl present in 57.2 g = ?

Solution:

1.6% of 57.2 g NaCl:

1.6/100× 57.2 g

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So in 57.2 g 1.6% of NaCl is 0.92 g.

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4 years ago