Answer:
-153.18 kj
Explanation:
Given data:
Heat capacity of burner = 345 j/°C
Initial temperature = 467°C
Final temperature = 23°C
Heat produced = ?
Solution:
Formula:
q = cΔT
q = heat absorbed or released
c = heat capacity
ΔT = change in temperature
ΔT = 23°C - 467°C
ΔT = -444°C
q = cΔT
q = 345 j/°C × -444°C
q = -153180 J
joule to kj :
q = -153180 J × 1 kj/ 1000 j
q = -153.18 kj
Answer:
3.68 g
Explanation:
= 18 ÷ 44 = 0.4
2C2H2 + 5O2 → 4CO2 + 2H2O
2 : 5 : 4 : 2
0.409 (moles)
⇒ = 0.409 × 2 ÷ 4 = 0.2045 moles
⇒ = 0.2045 × 18 = 3.68 grams
I speak only english sorry
Answer:
1 × 10⁸ He atoms
Explanation:
Step 1: Given data
- Diameter of a helium atom (d): 1 × 10² pm
- Total distance to be covered (D): 1 cm
Step 2: Convert "d" to meters
We will use the conversion factor 1 m = 10¹² pm.
1 × 10² pm × (1 m / 10¹² pm) = 1 × 10⁻¹⁰ m
Step 3: Convert "D" to meters
We will use the conversion factor 1 m = 100 cm.
1 cm × (1 m / 100 cm) = 0.01 m
Step 4: Calculate the number of atoms of He required
We will use the following expression.
D/d = 0.01 m / 1 × 10⁻¹⁰ m = 1 × 10⁸