Answer:
- 0.674 kJ.
Explanation:
The equation used to solve this problem is:
Q = mCΔT
where,
Q = amount of heat
m = mass of the substance
C = specific heat capacity
ΔT = change in temperature
= Temp.f - Temp.i
Given:
m = 29.2 g
Temp.i = 79°C
Temp.f = 27°C
Cp(iron) = 0.444 J/g.K
Q = mCΔT
ΔT = 27.0°C - 79.0°C
= -52°C
= 29.2 * 0.444 * -52
Q = - 674.17 J
= 0.674 kJ.
You are given
300 grams of FeCr2O7. You are required to get the mass of O2 in grams. The first
thing to do is to find a reaction between FeCr2O7 and O2. The balanced chemical
reaction is 2Fe + 6Cr + 21/2O2 -> Fe2(Cr2O7)3. The molar mass of Fe2(Cr2O7)3
is 759.65 grams per mole and 32 grams per mole for O2.
<span>
300g Fe2(Cr2O7)3
(1 mol Fe2(Cr2O7)3/759.65 g Fe2(Cr2O7)3)(21/2 mol O2/1 mole Fe2(Cr2O7)3)(32 g
O2/1 mole O2) = <u>132.7 g O2</u></span>
Explanation:
A 57.9 g sample of glass is cooled by 2.70'C how much heat does it release
1560
Chromatography is a way of separating a mixture of chemicals which are in gas or liquid form. when the paper absorbs the liquid, the different colours from the colouring pencils will not be separated because they are insoluble solid pieces,also because they are solid the colours will not be able to creep up the paper which is why chromatography can not be used to separate different coloured pencils.
Answer:
A. to cure human diseases
Explanation: