Explanation:
I hope this one is useful, I will complete later
Answer:
9028.8 J
Explanation:
The equation for working out the amount of thermal energy required is q = m c Δ T , where q is the amount of energy, m is the mass being heated up in grams, c is the specific heat capacity of what you're heating up in joules per gram per kelvin, and Δ T is the change in temperature in Kelvin.(Change in temperature will always give the same value,no matter Celsius or Kelvin)
mass = 27g, assuming specific heat capacity of water is 4.18 J/g*K, and the change in temperature is 90-10(=80) , the energy needed to raise : 80 × 27 × 4.18 = 9028.8 J
Answer:
16.89g of PbBr2
Explanation:
First, let us calculate the number of mole of Pb(NO3)2. This is illustrated below:
Molarity of Pb(NO3)2 = 0.595M
Volume = 77mL = 77/1000 = 0.077L
Mole =?
Molarity = mole/Volume
Mole = Molarity x Volume
Mole of Pb(NO3)2 = 0.595x0.077
Mole of Pb(NO3)2 = 0.046mol
Convert 0.046mol of Pb(NO3)2 to grams as shown below:
Molar Mass of Pb(NO3)2 =
207 + 2[ 14 + (16x3)]
= 207 + 2[14 + 48]
= 207 + 2[62] = 207 +124 = 331g/mol
Mass of Pb(NO3)2 = number of mole x molar Mass = 0.046 x 331 = 15.23g
Molar Mass of PbBr2 = 207 + (2x80) = 207 + 160 = 367g/mol
Equation for the reaction is given below:
Pb(NO3)2 + CuBr2 —> PbBr2 + Cu(NO3)2
From the equation above,
331g of Pb(NO3)2 precipitated 367g of PbBr2
Therefore, 15.23g of Pb(NO3)2 will precipitate = (15.23x367)/331 = 16.89g of PbBr2
