4.00 moles of sodium has a mass of 91.96 grams.
To find an element's molar mass, you can use its atomic weight.
That would be phosphorus. It’s electron configuration is 1s^2 2s^2 2p^6 3s^2 3p^3
Answer:
26.7°C
Explanation:
Using the formula; Q = m × c × ΔT
Where; Q = amount of heat
m = mass
c = specific heat
ΔT = change in temperature
In this question involving iron placed into water, the Qwater = Qiron
For water; m= 50g, c = 4.18 J/g°C, Initial temp= 25°C, final temp=?
For iron; m = 30.5g, c = 0.449J/g°C, Initial temp= 52.7°C, final temp=?
Qwater = -(Qiron)
m × c × ΔT (water) =- {m × c × ΔT (iron)}
50 × 4.18 × (T - 25) = - {30.5 × 0.449 × (T - 52.7)}
209 (T - 25) = - {13.6945 (T - 52.7)}
209T - 5225 = -13.6945T + 721.7
209T + 13.6945T = 5225 + 721.7
222.6945T = 5946.7
T = 5946.7/222.6945
T = 26.7
Hence, the final temperature of water and iron is 26.7°C
Answer:
A) 14. 25 × 10²³ Carbon atoms
B) 34.72 grams
Explanation:
1 molecule of Propane has 3 atoms of Carbon and 8 atoms of Hydrogen.
The sample has 3.84 × 10²⁴ H atoms.
If 8 atoms of Hydrogrn are present in 1 molecule of propane.
3.84 × 10²⁴ H atoms are present in

<u>= 4.75 × 10²³ molecules of Propane</u>.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
No. of Carbon atoms in 1 molecule of propane = 3
=> C atoms in 4.75× 10²³ molecules of Propane = 3 × 4.75 × 10²³
<u>= 14.25 × 10²³ </u>
<u>________________________________________</u>
<u>Gram</u><u> </u><u>Molecular</u><u> </u><u>Mass</u><u> </u><u>of</u><u> </u><u>Propane</u><u>(</u><u>C3H8</u><u>)</u>
= 3 × 12 + 8 × 1
= 36 + 8
= 44 g
1 mole of propane weighs 44g and has 6.02× 10²³ molecules of Propane.
=> 6.02 × 10²³ molecules of Propane weigh = 44 g
=> 4. 75 × 10²³ molecules of Propane weigh =



<u>= 34.72 g</u>