Answer:
1.053×10²⁴ atoms of gold
Explanation:
Hello,
Gold nugget are usually the natural occurring gold and they contain 85% - 90% weight of pure gold.
In this question, we're required to find the number of atoms in 344.75g of a gold nugget.
We can use mole concept relationship between Avogadro's number and molar mass.
1 mole = molar mass
Molar mass of gold = 197 g/mol
1 mole = Avogadro's number = 6.022 × 10²³ atoms
Number of mole = mass / molar mass
Mass = number of mole × molar mass
Mass = 1 × 197
Mass = 197g
197g is present in 6.022×10²³ atoms
344.75g will contain x atoms
x = (344.75 × 6.022×10²³) / 197
X = 1.053×10²⁴ atoms
Therefore 344.75g of gold nugget will contain 1.053×10²⁴ atoms of gold
The mass of HCl that is contained in the solution is 147 g HCl
Why?
To find the mass of HCl we have to apply what is called a conversion factor. In a conversion factor we put the units we don't want at the bottom, and the ones we want at the top.
For this question, we want to go from liters of solution to mass of HCl, and the conversion factor is laid out as follows:
Have a nice day!
#LearnwithBrainly
The best way to obtain pure, solid household salt from a solid mixture of household salt and sand is to "add water, stir, filter and evaporate the filtrate".
<u>Option: C</u>
<u>Explanation:</u>
The salt and sand can be separated on the basis of solubility, as we know the salt is chemically known as sodium chloride, which have good solubility in water. The most general method is the mixture is taken into a flask or beaker and water is added with stirring, where salt get dissolved and sand remain as it is, because NaCl is capable enough to form hydrogen bonding with water, while sand have absence of such property. Then this solution containing insoluble sand is filtered by using filter paper. The sand is received in filter paper while filtrate in beaker is evaporated by boiling it in order to receive salt as residue.
Answer:
the epigenetic perspective. ... Such variation among organisms with virtually identical chromosomal DNA sequences has largely been attributed to the effects of environment.Explanation:
The given condition is STP, under this condition, gas has a rule of 22.4 L per mole. And the given equation is already balanced. The ratio of mole number is the same as the ratio of the volume and is also the same as the ratio of coefficients. So the answer is 4.0 liters.
