Answer:
3.6g
Explanation:
2 moles of water gives 1 mole of oxygen
2(h2o)=1(o2)
2(molar mass of h2o)=1(molar mass of oxygen molecule)
2(18)=1(16×2)
36=32
3.6=x
cross multiply
3.6×32=36× x
115.2=36x
x=115.2÷36
x=3.6g
STP stands for the Standard Temperature and Pressure. The standard temperature is 273 Kelvin or 0 degrees Celcius or 32 Fahrenheit and the standard pressure is 1 atm pressure or 760 mmHg, or 10,325 Pascals. STP is most commonly used when performing calculations on gases.
How much heat is necessary to supply 2 kilograms of aluminum to raise its temperature by 20 ° C?
Answer:
36000J
Explanation:
Given parameters:
Mass of aluminum = 2kg = 2000g
Temperature rise = 20°C
Unknown:
Amount of heat needed for the temperature change = ?
Solution:
The amount of heat needed to cause this temperature rise is given as;
H = m c (T₂ - T₁)
H is the amount of heat
m is the mass
c is the specific heat of aluminum = 0.9J/g°C
Insert the parameters and solve;
H = 2000 x 0.9 x 20 = 36000J
You would have 7 hydrogen and 2 oxygen atoms.
