Answer:H2=11.4g
CH4=28.6g
Explanation:The complete combustion of the two gases can be represented by a balanced reaction below
1. CH4 +2O2___CO2+2H2O
2.2H2+O2___2H2O
Combining the two we have CH4 +2H2+3O2___
CO2+4H2O
Since the mixture contains 40gof CH4 and 2, therefore 20g of CH4 and 8g of H2 combines.
Calculated from their molecular Mass i.e CH4 12+4×2)=20 and 2H2= 2×2×2=8g
Mass of CH4=20/28×40=28.6g
2H2=8/28×40=11.4g
Answer:
1) When 6.97 grams of sodium(s) react with excess water(l), 56.0 kJ of energy are evolved.
2) When 10.4 grams of carbon monoxide(g) react with excess water(l), 1.04 kJ of energy are absorbed.
Explanation:
1) The following thermochemical equation is for the reaction of sodium(s) with water(l) to form sodium hydroxide(aq) and hydrogen(g).
2 Na(s) + 2H₂O(l) ⇒ 2NaOH(aq) + H₂(g) ΔH = -369 kJ
The enthalpy of the reaction is negative, which means that 369 kJ of energy are evolved per 2 moles of sodium. The energy evolved for 6.97 g of Na (molar mass 22.98 g/mol) is:
2) The following thermochemical equation is for the reaction of carbon monoxide(g) with water(l) to form carbon dioxide(g) and hydrogen(g).
CO(g) + H₂O(l) ⇒ CO₂(g) + H₂(g) ΔH = 2.80 kJ
The enthalpy of the reaction is positive, which means that 2.80 kJ of energy are absorbed per mole of carbon monoxide. The energy evolved for 10.4 g of CO (molar mass 28.01 g/mol) is:
C. HNO₃(aq) + KOH(aq) → KNO₃(aq) + H₂O
From among the subatomic particles available, we determine which element is presented by using the number of protons. The 49th element in the periodic table is Indium (In). The chemical symbol is In-62. 62 is the number representing the number of neutrons .
Answer: In-62
Sulfur will float, and iron will sink because each will retain its properties.
“Iron will float, and sulfur will sink because each will lose its properties” is <em>incorrect</em>. A substance will lose its properties only if it reacts to form a new substance.
“Both will float because they are physically mixed” is <em>incorrect</em>. The substances in a mixture retain their properties.
“Both will float because they react chemically” is <em>incorrect</em>. Iron and sulfur do not react at room temperature. Even if they did, the iron sulfide would sink.
