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
Answer:
The molarity of this sugar solution in water is 2.18 M
Explanation:
Step 1: Data given
Mass of sugar (C12H22O11) = 186.55 grams
Molar mass of C12H22O11 = 342.3 g/mol
Volume of water = 250.0 mL = 0.250 L
Step 2: Calculate moles sugar
Moles sugar = mass sugar / molar mass sugar
Moles sugar = 186.55 grams / 342.3 g/mol
Moles sugar = 0.545 moles
Step 3: Calculate molarity of the sugar solution
Molarity = moles sugar / volume of water
Molarity = 0.545 moles / 0.250 L
Molarity = 2.18 MThe molarity of this sugar solution in water is 2.18 M
Explanation:
Solubility is determined by the principle , "like dissolves like" .
i.e. , if a compound is polar then it will dissolve in a polar compound only , and
if a compound is non - polar then it will dissolve in a non - polar compound only .
Hence , from the question ,
Water is a polar molecule , and hence it will dissolve only the polar molecule , i.e. , from the given options the polar molecule is , iii. K₂SO₄
Hexane , is a non - polar molecules , hence it will dissolve only the non polar molecule , i.e. , from the given options the non polar molecule is i. Butane .
Answer:
6.24 x 10-3 M
Explanation:
Hello,
In this case, for the given dissociation, we have the following equilibrium expression in terms of the law of mass action:
![Ka=\frac{[H_3O^+][BrO^-]}{[HBrO]}](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BH_3O%5E%2B%5D%5BBrO%5E-%5D%7D%7B%5BHBrO%5D%7D)
Of course, water is excluded as it is liquid and the concentration of aqueous species should be considered only. In such a way, in terms of the change 
, we rewrite the expression considering an ICE table and the initial concentration of HBrO that is 0.749 M:
Thus, we obtain a quadratic equation whose solution is:
Clearly, the solution is 0.00624 M as no negative concentrations are allowed, so the concentration of BrO⁻ is 6.24 x 10-3 M.
Best regards.
It's a cube so the volume = edge^3
Volume = 2.5^3 cm^3 = 15.625 cm^3
density = mass / volume = 42.20 / 15.625 = 2.70 You have 3 places of accuracy.
density of object = 2.70 grams / cm^3 <<<<=== answer.
