Chemical reactions are a change in substance while nuclear is destruction
<h3>
Answer:</h3>
1.93 g
<h3>
Explanation:</h3>
<u>We are given;</u>
The chemical equation;
2C₂H₆(g) + 7O₂(g) → 4CO₂(g) + 6H₂O(l) ΔH = -3120 kJ
We are required to calculate the mass of ethane that would produce 100 kJ of heat.
- 2 moles of ethane burns to produce 3120 Kilo joules of heat
Number of moles that will produce 100 kJ will be;
= (2 × 100 kJ) ÷ 3120 kJ)
= 0.0641 moles
- But, molar mass of ethane is 30.07 g/mol
Therefore;
Mass of ethane = 0.0641 moles × 30.07 g/mol
= 1.927 g
= 1.93 g
Thus, the mass of ethane that would produce 100 kJ of heat is 1.93 g
Because it tilts on its axis
Answer:
7 valence electrons.
Explanation:
Oxygen lies in period 2 and group 16 of the periodic table. It is eighth element on the periodic table. Its symbol is O.
Its electronic configuration is given by:
16 = 2,8,6
It has 6 valance electrons. Its valancy is -2. It means can share share and it can gain 2 electron to get stability.
Hence, The element oxygen has <u>7</u> valence electrons.
Energy absorbed by Iron block E (iron) = 460.5 J
Energy absorbed by Copper block E (Copper) = 376.8 J
<u>Explanation:</u>
To find the heat absorbed, we can use the formula as,
q = m c ΔT
Here, Mass = m = 10 g = 0.01 kg
ΔT = change in temperature = 400 - 300 = 100 K = 100 - 273 = -173 °C
c = specific heat capacity
c for iron = 460.5 J/kg K
c for copper = 376.8 J/kg K
Plugin the values in the above equation, we will get,
q (iron) = 0.01 kg × 460.5 J/kg K × 100 K
= 460.5 J
q (copper) = 0.01 kg × 376.8 J/kg K × 100 K
= 376.8 J
