Answer:
1.17 grams
Explanation:
Let's consider the balanced equation for the combustion of ethylene.
C₂H₄(g) + 3 O₂(g) → 2 CO₂(g) + 2 H₂O(l)
We can establish the following relations:
- 1411 kJ are released (-1411 kJ) when 1 mole of C₂H₄ burns.
- The molar mass of C₂H₄ is 28.05 g/mol.
The grams of C₂H₄ burned to give 59.0 kJ of heat (q = -59.0 kJ) is:
Answer:
B
Explanation:
four electron in atom in cal
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Hope this helps
Forces are defined by both strength and direction.
Avogadro's number is 1 mol = 6.02 * 10^23 elements
It means that 1 mol of atoms is 6.02 * 10^23 atoms
1 mol of atoms = 6.02 * 10^23 atoms
From there, if you divide both sides by 1 mol of atoms, you get
1 = 6.02 * 10^23 atoms / 1 mol of atoms.
That means, that to pass from a number of moles of atoms to number of atoms you have to multipby by the conversion factor
6.02*10^23 atoms Al/ 1 mol Al
That is the second option of the list.
