Answer:
5.5moles
Explanation:
CaC2 + 2H2O —> Ca(OH)2 + C2H2
From the equation, the following were observed:
1mole of CaC2 reacted to produced 1mol of C2H2.
Therefore, 5.5moles of CaC2 will also produce 5.5moles of C2H2
Answer: Elastic
Explanation: Both Objects had there momentum and kinetic energy conserved.
Answer:
Possible lowest volume = 0.19 cm
Possible highest volume = 0.21 cm
Explanation:
given data
volumetric pipette uncertainty = 0.01 cm³
total volume = 0.20 cm³
solution
we will get here Possible lowest and highest volume that is express as
Possible lowest volume = total volume - uncertainty .....................1
Possible highest volume = total volume + uncertainty ....................2
put here value in both equation and we get
Possible lowest volume = 0.20 cm - 0.01 cm
Possible lowest volume = 0.19 cm
and
Possible highest volume = 0.20 cm + 0.01 cm
Possible highest volume = 0.21 cm
Answer:
The concentration of sodium chloride in an aqueous solution that is 2.23 M and that has a density of 1.01 g/mL is 12.90% by mass
Explanation:
2.23 M aqueous solution of NaCl means there are 2.23 moles of NaCl in 1000 mL of solution.
We know that density is equal to ratio of mass to volume.
Here density of solution is 1.01 g/mL.
So mass of 1000 mL solution = (
) g = 1010 g
molar mass of NaCl = 58.44 g/mol
So mass of 2.23 moles of NaCl = (
) g = 130.3 g
% by mass is ratio of mass of solute to mass of solution and then multiplied by 100.
Here solute is NaCl.
So % by mass of 2.23 M aqueous solution of NaCl = 
% = 12.90%
<span>128 g/mol
Using Graham's law of effusion we have the formula:
r1/r2 = sqrt(m2/m1)
where
r1 = rate of effusion for gas 1
r2 = rate of effusion for gas 2
m1 = molar mass of gas 1
m2 = molar mass of gas 2
Since the atomic weight of oxygen is 15.999, the molar mass for O2 = 2 * 15.999 = 31.998
Now let's subsitute the known values into Graham's equation and solve for m2.
r1/r2 = sqrt(m2/m1)
2/1 = sqrt(m2/31.998)
4/1 = m2/31.998
127.992 = m2
So the molar mass of the unknown gas is 127.992 g/mol.
Rounding to 3 significant figures gives 128 g/mol</span>
