Answer:
The correct answer is A. Barium Chloride
Explanation:
<span>The chemical formula of Helium is He.
Question 1 :
Given n = 1.11 x 10^-6
To get no. of the particle,
No of particle = no. of mole x Avogadro Constant
p = n x NA
1 mol of Helium = 6.02 x 10^23
No of atoms = (6.02 x 10^23) x (1.11 x 10^-6)
= 6.66 x 10^17
................................
Question 2 :
Given p = 4.29x10^21
p = n x NA
4.29 x 10^21 = n x (6.02 x 10^23)
(4.29 x 10^21) / (6.02 x 10^23) = n
n = Approximately 7.126 x 10^-3
Hope the answer is right :)</span>
Answer:
Given
mass of solute (m) =20.5g
mass of solvent( ms) =155g
solution
malality =mX1000/mrxms
M=20.5x1000/62x155
M=2.1332
Answer:
\large \boxed{\textbf{609 kJ}}
Explanation:
The formula for the heat absorbed is
q = mCΔT
Data:
m = 2.07 kg
T₁ = 23 °C
T₂ = 191 °C
C = 1.75 J·°C⁻¹g⁻¹
Calculations:
1. Convert kilograms to grams
2.07 kg = 2070 g
2. Calculate ΔT
ΔT = T₂ - T₁ = 191 - 23 = 168 °C
3. Calculate q
The answer is 5.32 × 10²³ molecules
<span>Avogadro's number is the number of units (atoms, molecules) in 1 mole of substance:
</span>6.023 <span>× 10²³ units per 1 mole
We have 0.883 moles.
If 1 mole has </span>6.023 × 10²³ molecules, 0.883 moles will have x molecules:
1 mole : 6.023 × 10²³ molecules = 0.883 moles : x
x = 6.023 × 10²³ molecules * 0.883 moles : 1 mole = 5.32 × 10²³ molecules
