Answer:
<em>- 0.0413°C ≅ - 0.041°C (nearest thousands).</em>
Explanation:
- Adding solute to water causes the depression of the freezing point.
<em>ΔTf = Kf.m,</em>
Where,
ΔTf is the change in the freezing point.
Kf is the freezing point depression constant (Kf = 1.86 °C/m).
m is the molality of the solution.
<em>Molality is the no. of moles of solute per kg of the solution.</em>
- <em>no. of moles of solute (glucose) = mass/molar mass</em> = (8.44 g)/(180.156 g/mol) = <em>0.04685 mol.</em>
<em>∴ molality (m) = no. of moles of solute/kg of solvent</em> = (0.04685 mol)/(2.11 kg) = <em>0.0222 m.</em>
∴ ΔTf = Kf.m = (1.86 °C/m)(0.0222 m) = 0.0413°C.
<em>∴ The freezing point of the solution = the freezing point of water - ΔTf </em>= 0.0°C - 0.0413°C = <em>- 0.0413°C ≅ - 0.041°C (nearest thousands).</em>
Answer:
1.25 hours or 75 minutes or 1 hour and 15 minutes
Explanation:
Answer:
option D= Gold (I) nitride
Explanation:
The name of the given compound is gold(I) nitride.
Molar mass can be determine by following way:
molar mass Au3N = (molar mass of gold × 3) + (molar mass of nitrogen)
molar mass Au3N = (196.97 × 3 ) + ( 14 )
molar mass of Au3N = 590.91 g/mol + 14 g/mol
molar mass of Au3N = 604.91 g/mol
The nitrogen has valency of -3 so three Au(+1) will require while the valency of Au is (1+) one nitrogen will require to make the compound overall neutral.
Au3N
3(1+) + (-3) = 0
+3 - 3 = 0
0 = 0
The overall charge is 0, the compound will be neutral.
Answer:
52.15 × 10²³ atoms
Explanation:
Given data:
Number of moles = 8.66 mol
Number of atoms = ?
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
1 mole = 6.022 × 10²³ atoms
8.66 mol × 6.022 × 10²³ atoms / 1mol
52.15 × 10²³ atoms
Answer:
Periods have consecutive atomic number as they are in a row and groups are vertical meaning they are in a column and groups have similar properties
