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sladkih [1.3K]
3 years ago
9

In 1928, 47.5 g of a new element was isolated from 660 kg of the ore molybdenite. the percent by mass of this element in the ore

was:
Chemistry
2 answers:
vitfil [10]3 years ago
8 0

To take the percent by mass of this element, we use the formula:

% mass = (mass of element / mass of ore) * 100%

% mass = (47.5 g / (660 kg * 1000 g / kg)) * 100*

<span>% mass = 7.20 x 10^-3 %</span>

patriot [66]3 years ago
3 0

<u>Answer:</u> The mass percent of element in the ore is 0.0072 %

<u>Explanation:</u>

To calculate the mass percentage of element in ore, we use the equation:

\text{Mass percent of element}=\frac{\text{Mass of element}}{\text{Mass of ore}}\times 100

Mass of element = 47.5 g

Mass of ore = 660 kg = 660000 g    (Conversion factor:  1 kg = 1000 g)

Putting values in above equation, we get:

\text{Mass percent of element}=\frac{47.5g}{660000g}\times 100=0.0072\%

Hence, the mass percent of element in the ore is 0.0072 %

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