How many molecules are in a sample of sucrose that has a mass of 15.0 G

Which pair of elements can be used to determine the age of a fossil that is over one billion years old?

lakkis [162]

Answer:

Explanation:

There are some radioactive nuclides can be used to measure time on an archeological scale. One is the best example of this is radiocarbon dating. This process is based on the ratio of caebon-14 to carbon-12 in the atmosphere which is relatively constant.

The half time of C-14 5730 years

Carbon-14 is a radioactive nucleus. It has a half-life of 5730 years.

All living tissues like plants and animal absorbed carbon-12 along with carbon-14 with same ratio of caebon-14 to carbon-12 in the atmosphere.

Carbon-14 dating is based on the ratio of carbon-14 to carbon-12 in the atmosphere which is relatively constant

3 0

3 years ago

Read 3 more answers

If the gold in the crown was mixed with a less-valuable metal like bronze or copper, how would that affect its density?

Sindrei [870]

Answer: If the gold in the crown was mixed with a less-valuable metal such as bronze of copper then this affects its density by making it to weigh even more and if it weighs more then it has less of chance to float. Observe: Drag each of the crowns into the liquid.

Explanation:

6 0

3 years ago

PLSS CAN ANYONE HELP ME..

rodikova [14]

Answer:

there is two mixture homogeneous and heterogeneous mixture

ok

7 0

3 years ago

A tank at is filled with of sulfur tetrafluoride gas and of sulfur hexafluoride gas. You can assume both gases behave as ideal g

dangina [55]

The question is incomplete, the complete question is:

A 7.00 L tank at $21.4^oC$ is filled with 5.43 g of sulfur hexafluoride gas and 14.2 g of sulfur tetrafluoride gas. You can assume both gases behave as ideal gases under these conditions. Calculate the mole fraction and partial pressure of each gas. Round each of your answers to significant digits.

Answer: The mole fraction of sulfur hexafluoride is 0.221 and that of sulfur tetrafluoride is 0.779

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ ......(1)

For sulfur hexafluoride:

Given mass of sulfur hexafluoride = 5.43 g

Molar mass of sulfur hexafluoride = 146.06 g/mol

Putting values in equation 1, we get:

$\text{Moles of sulfur hexafluoride}=\frac{5.43g}{146.06g/mol}=0.0372mol$

For sulfur tetrafluoride:

Given mass of sulfur tetrafluoride = 14.2 g

Molar mass of sulfur tetrafluoride = 108.07 g/mol

Putting values in equation 1, we get:

$\text{Moles of sulfur tetrafluoride }=\frac{14.2g}{108.07g/mol}=0.1314mol$

Total moles of gas in the tank = [0.0372+ 0.1314] mol = 0.1686 mol

Mole fraction is defined as the moles of a component present in the total moles of a solution. It is given by the equation:

$\chi_A=\frac{n_A}{n_A+n_B}$ .....(2)

where n is the number of moles

Putting values in equation 2, we get:

$\chi_{SF_6}=\frac{0.0372}{0.1686}=0.221$

$\chi_{SF_4}=\frac{0.1314}{0.1686}=0.779$

Hence, the mole fraction of sulfur hexafluoride is 0.221 and that of sulfur tetrafluoride is 0.779

7 0

3 years ago

Why is the composition of Earth's atmosphere different from the composition of the atmospheres of Venus and Mars? A. Venus, Mars

rewona [7]

Answer:

they all have different chemical compositions from earth

Venus is more filled with carbon dioxide and nitrogen

earth is filled more with oxygen and nitrogen

mars is filled more with carbon dioxide and carbon monoxide

so ur answer is C

it cant be B as scientists and NASA are still in the look out for life, D has nothing to do with chemicals and atmosphere, and its not A cuz they all dont have the same similiar chemical.

~batmans wife dun dun dun....

6 0

4 years ago