Answer:
The balanced equation for this reaction will be
→ 
We can see that 1 mole of methane requires 4 moles of fluorine but we have 0.41 moles of CH4 and 0.56mole of F2
So using the unitary method we will get that
- 1 mole of CH4 → 4 mole of 4 mole of fluorine
- 0.41 mole of methane → 4*0.41 = 1.64 mole of fluorine for complete reaction
but we have only 0.56 mole of fluorine that means fluorine is the limiting reagent and the product will only be formed by only this amount of fluorine.
- 4 moles of fluorine → 1 mole of CF4
- 0.56 mole →
= 0.14mole of CF4
- 4 moles of fluorine → 4 moles of HF
- 0.56 mole of fluorine → 0.56 mole of HF
now to find the heat released we have the formula as
DELTA H = n * Delta H of product - n *delta H of reactant
where n is the moles of the reactant and product.
note: since no information is given about the enthalpies of the species we leave it on general equation also you need to add the product side enthalpy of the species present and similarly on the product side.
Hi!
The answer is breathing.
Protozoans are organisms that can multiply themselves in humans, and serious infections can develop from one organism. The most frequently transmission methods are contaminated food or fecal contact. Dog bites inoculate bacteria into deep tissue, and they also serve as a transmission method.
Breathing is not considered to be likely to transmit protozoan infection because protozoans rarely develop in the respiratory tract.
I don’t understand the question
The balanced equation for the above reaction is as follows;
Na₂SO₄ + BaCl₂ --> BaSO₄ + 2NaCl
Na₂SO₄ reacts with BaCl₂ in the molar ratio 1:1
Number of Na₂SO₄ moles - 10.0 g / 142.1 g/mol = 0.0704 mol
Number of BaCl₂ moles - 10.0 g / 208.2 g/mol = 0.0480 mol
this means that 0.0480 mol of each reactant is used up, BaCl₂ is the limiting reactant and Na₂SO₄ has been provided in excess.
stoichiometry of BaCl₂ to BaSO₄ is 1:1
number of BaSO₄ moles formed - 0.0480 mol
Mass of BaSO₄ - 0.0480 mol x 233.2 g/mol = 11.2 g
theoretical yield is 11.2 g but the actual yield is 12.0 g
the actual product maybe more than the theoretical yield of the product as the measured mass of the actual yield might contain impurities.
percent yield - 12.0 g/ 11.2 g x 100% = 107%
this is due to impurities present in the product or product could be wet.
Answer: B) 46.7% Si and 53.3% O
Explanation:
To calculate the mass percent of element in a given compound, we use the formula:

Mass of quartz
= 5.05 g
Mass of silicon = 2.36 g
Mass of oxygen = Mass of quartz
- mass of silicon = 5.05g - 2.36 g = 2.69 g


Thus the percentages of silicon and oxygen in quartz are B) 46.7% Si and 53.3% O