The correct answer is 2.70 × 10² g or 270 g.
It is given, that the density of a metal is 9.80 g/ml.
Let the mass of a sample of metal be x.
The sample of metal is dropped in 28.9 ml of water, due to which the volume of the water increases to 56.4 ml.
In order to calculate the mass of a metal, there is a need to use the formula, mass = density * volume
Mass = (9.80 g/ml) (56.4 ml - 28.9 ml)
= (9.80 g/ml) (27.5 ml)
= 2.70 × 10² g or 270 g
Answer:
Explanation:
molecular weight of creatinine = 131
1 mg of creatinine = 1 x 10⁻³ / 131 = 7.63 x 10⁻⁶ mole of creatinine.
volume of solution = .1 L
mass of blood solution = .1 x 1025
= 102.5 g
mass of solvent = 102.5 g approximately
= .1025 kg
molality = mole of solute / mass of solvent in kg
= 7.63 x 10⁻⁶ / .1025 kg
= 74.44 x 10⁻⁶ .
Osmotic pressure :---
π V / T = nR π is osmotic pressure , V is volume of solution in liter , T is absolute temperature , n is molality .
π x .1 / 298 = 74.44 x 10⁻⁶ x .082
π = 18.19 x 10⁻³ atm
Answer:
3.23945533x
g
Explanation:
mass of 1 atom Pt = mass of a mole of atom Pt / 6.022 x 
= 195.08/6.022 x = 3.23945533xg
The solution contains 39.4% of LiF. Assume that the solution is 100ml. The molar mass of LiF is 25.939, the amount of LiF in mole would be: 100ml * 1g/ml * 39.4%/ 25.939g/mol= 1.52 mol LiF
Then the mass of the water would be: 100gram- 39.4g= 60.6g
If the molar mass of water is 18.015 the mole of the water would be: 60.6g/ 18.015g/mol= 3.36 mol
.
The mole fraction would be:1.52 mol/ 1.52+3.36= 0.339
Answer:Hess's law states that the change of enthalpy in a chemical reaction (i.e. the heat of reaction at constant pressure) is independent of the pathway between the initial and final states. ... Hess's law allows the enthalpy change (ΔH) for a reaction to be calculated even when it cannot be measured directly.
Explanation:
