Answer:
3.43 %
Explanation:
We need to calculate first the number of moles of CeO2 produced in the combustion. Given its formula we know how many moles of Ce atom are present. From there calculate the mass this number of moles this represent and then one can calculate the percentage.
0.1848 g CeO2 x 1 mol CeO2/172.114g = 0.00107 mol CeO2
0.00107 mol CeO2 x 1 mol Ce/ 1 mol CeO2 = 0.00107 mol Ce
.00107 mol Ce x 140.116 g Ce/ mol = 0.150 g Ce
0.150 g Ce/ 4.3718 g sample x 100 = 3.43 %
The intended sense is that of a reaction that depends on absorbing heat if it is to proceed. The opposite of an endothermic process is an exothermic process, one that releases "gives out" energy in the form of heat
Answer:
1. Gases can be easily liquefied into very small volumes and stored in liquid form Eg in LPGA cylinders and used in homes.
2. Balloons can be easily filled with air.
Answer:
2.94x10²² atoms of Cu
Explanation:
We must work with NA to solve this, where NA is the number of Avogadro, number of particles of 1 mol of anything.
Molar mass Cu = 63.55 g/mol
Mass / Molar mass = Mol → 3.11 g / 63.55 g/m = 0.0489 moles
1 mol of Cu has 6.02x10²³ atoms of Cu
0.0489 moles of Cu, will have (0.0489 .NA)/ 1 = 2.94x10²² atoms of Cu
There can be three possible answers to this question: the amount of moles of SO₂ gas needed to react with 6.41 mol H₂S, and the amount of S and H₂O gas produced.
Amount of SO₂:
6.41 mol H₂S (1 mol SO₂/2 mol 2 mol H₂S) = <em>3.205 moles SO₂ gas</em>
Amount of S:
6.41 mol H₂S (3 mol S/2 mol 2 mol H₂S) =<em> 9.615 moles S solid</em>
Amount of H₂O:
6.41 mol H₂S (2 mol H₂O/2 mol 2 mol H₂S) = <em>6.41 moles H₂O gas</em>
