Recorded by a seismograph.
Cooper cannot be broken down into a simpler substance since it is an element meaning it had its own atoms.
Answer:
-26.125 kj
Explanation:
Given data:
Mass of water = 250.0 g
Initial temperature = 30.0°C
Final temperature = 5.0°C
Amount of energy lost = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = T2 - T1
ΔT = 5.0°C - 30.0°C
ΔT = -25°C
Specific heat of water is 4.18 j/g.°C
Now we will put the values in formula.
Q = m.c. ΔT
Q = 250.0 g × 4.18 j/g.°C × -25°C
Q = -26125 j
J to kJ
-26125 j ×1 kj /1000 j
-26.125 kj
Answer:
Molarity = 0.3 M
Explanation:
Given data:
Moles of NaOH = 0.720 mol
Volume of water = 2.40 L
Molarity = ?
Solution:
Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.
Formula:
Molarity = number of moles of solute / L of solution
Molarity = 0.720 mol / 2.40 L
Molarity = 0.3 mol/L
Molarity = 0.3 M
actual yield of ethanol = 305.0g
molar mass of sucrose = 342g
molar mass of ethanol =46g
mass of sucrose = 665g
mole of sucrose = mass / molar mass = 665/342
mole of sucrose =1.9 mole
sucrose : C2H5OH
1 : 4
1.9 : 1.9x4 =7.6 mole of C2H5OH are formed
mass (therotical yield ) of C2H5OH= mole x mass
mass (therotical yield ) of C2H5OH= 7.6 x 46 = 349.6g
percent yields of ethanol = actual /therotical x100
=305/349.6x100 = 87.24 %
