Answer:
Option A. 3.3
Explanation:
The following data were obtained from the question:
Input force = 150 N
Output force = 500 N
Mechanical advantage (MA) =.?
Mechanical advantage can be defined as force output divided by force input i.e
Mechanical advantage (MA) = force output / force input
With the above formula, we can obtain the mechanical advantage of the pulley as shown below:
Input force = 150 N
Output force = 500 N
Mechanical advantage (MA) =.?
MA = force output / force input
MA= 500/150
MA = 3.3
Thus, the mechanical advantage of the system is 3.3
Answer:
See explanation
Explanation:
Now, the equation of the reaction is;
Cu(s) + 2AgNO3(aq) --------> Cu(NO3)3 (aq) + 2Ag(s)
Number of moles of silver precipitate = 0.24/108 g/mol= 0.0022 moles
Number of moles of AgNO3 = 50/1000 * 0.050 = 0.0025 Moles
If 2 moles of AgNO3 yields 2 moles of Ag
Then 0.0025 moles of AgNO3 yields 0.0025 * 2/2 = 0.0025 moles of Ag
Number of moles of Cu = 2.00g/63.5 g/mol = 0.03 moles
If 1 mole of Cu yields 2 moles of Ag
0.03 moles of Cu yields 0.03 moles * 2/1 = 0.06 moles of Ag
Hence AgNO3 is the limiting reactant
Theoretical yield of Ag = 0.0025 moles of Ag * 108 = 0.27 g
Actual yield of Ag = 0.24 g
Percent yield = actual yield/theoretical yield * 100
Percent yield = 0.24/0.27 * 100
Percent yield = 88.8%
Let x gallon of pure alcohol added to 15 % mixture to make it upto 25 %
15 % alcohol of 20 gallon can be shown as
(15 /100) * 20 + x = (25 /100) (x +20)
3 + x = 0.25 x + 5
0.75 x = 2
X = 2.66 gallon
Hence, 2.66 gallon of pure alcohol need to added to 20 gallon 15 % alcohol to obtain 25 % solution.
Answer:
have the same number of atoms
Explanation:
Atoms of the same element have the same atomic number so the number of protons (and electrons) are same. But they have same or different mass number (like that for isotopes) . Different mass number will have different number of neutrons.
Answer:
ΔG = - 442.5 KJ/mol
Explanation:
Data Given
delta H = -472 kJ/mol
delta S = -108 J/mol K
So,
delta S = -0.108 J/mol K
delta Gº = ?
Solution:
The answer will be calculated by the following equation for the Gibbs free energy
G = H - TS
Where
G = Gibbs free energy
H = enthalpy of a system (heat
T = temperature
S = entropy
So the change in the Gibbs free energy at constant temperature can be written as
ΔG = ΔH - TΔS . . . . . . (1)
Where
ΔG = Change in Gibb’s free energy
ΔH = Change in enthalpy of a system
ΔS = Change in entropy
if system have standard temperature then
T = 273.15 K
Now,
put values in equation 1
ΔG = (-472 kJ/mol) - 273.15 K (-0.108 KJ/mol K)
ΔG = (-472 kJ/mol) - (-29.5 KJ/mol)
ΔG = -472 kJ/mol + 29.5 KJ/mol
ΔG = - 442.5 KJ/mol