sure its b but im preatty sur dont spell check me plz
It is B balance, because it has a 0,01 g divisions scale. The minimun division in A balance is only 0,1 g, i.e, decigram measurement.
<span>7.15 degrees C
The specific heat capacity of water is 4.1813 J/(g*K). So we have 3 values with the units kJ, g and J/(g*K). We can trivially convert from kJ to J by multiplying by 1000. And we want to get a result with the unit K (degrees Kelvin). So let's do it. First, let's cancel out the g unit by multiplying.
4.1813 J/(g*K) * 485 g = 2027.9305 J/K
Now we can cancel out the J unit by dividing. But if we divide by the energy, we'll be left with the reciprocal of K, not K. So instead divide by the J/K unit. So
14500 J / 2027.9305 J/K = 7.150146418 K
Rounding to 3 significant figures gives us 7.15 K.
And since degrees C and degrees K are the same size, the temperature will increase by 7.15 degrees C</span>
Answer:
41.54 grams of oxygen are required to burn 13.5 g of acetylene
Explanation:
The balanced reaction is:
2 C₂H₂ + 5 O₂ → 4 CO₂ + 2 H₂O
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
- C₂H₂: 2 moles
- O₂: 5 moles
- CO₂: 4 moles
- H₂O: 2 moles
Being the molar mass of the compounds:
- C₂H₂: 26 g/mole
- O₂: 32 g/mole
- CO₂: 44 g/mole
- H₂O: 18 g/mole
By reaction stoichiometry, the following mass quantities of each compound participate in the reaction:
- C₂H₂: 2 moles* 26 g/mole= 52 grams
- O₂: 5 moles* 32 g/mole= 160 grams
- CO₂: 4 moles* 44 g/mole= 176 grams
- H₂O: 2 moles* 18 g/mole= 36 grams
You can apply the following rule of three: if by stoichiometry 52 grams of acetylene react with 160 grams of oxygen, 13.5 grams of acetylene react with how much mass of oxygen?
mass of oxygen= 41.54 grams
<u><em>41.54 grams of oxygen are required to burn 13.5 g of acetylene</em></u>
<u><em></em></u>
57 degrees celcius is equal to 330 degrees kelvin
67.88 kPa is equal to 67880 Pa
85.3 liters is equal to 0.0853 m^3
Now, the equation we will use to solve this question is:
PV = nRT where:
P is the pressure of gas = 67880 Pa
V is the volume of gas = 0.0853 m^3
n is the number of moles we are looking for
R is the gas constant = 8.31441 J K-1<span> mol</span><span>-1
T is the temperature of gas = 330 degrees kelvin
Substitute with the givens in the above equation to get n as follows:
n = (PV) / (RT)
n = (67880*0.0853) / (8.31441*330)
n = 2.11 moles</span>
