Answer:
36.8 L
Explanation:
We'll begin by converting 80 °C to Kelvin temperature. This can be obtained as follow:
T(K) = T(°C) + 273
T(°C) = 80 °C
T(K) = 80 + 273
T(K) = 353 K
Finally, we shall determine the volume occupied by the helium gas. This can be obtained as follow:
Number of mole (n) = 1.27 moles
Temperature (T) = 353 K
Pressure (P) = 1 atm
Gas constant (R) = 0.0821 atm.L/Kmol
Volume (V) =?
PV = nRT
1 × V = 1.27 × 0.0821 × 353
V = 36.8 L
Thus, the volume occupied by the helium gas is 36.8 L
a) The reaction is exothermic since the overall enthalpy change is negative. this means that the system has lost energy to the environment, namely, the apparatus and due to drought.
b) We first calculate the number of moles in 3.55 grams of magnesium.
number of moles= mass/ atomic mass
=3.55/24
=0.1479 moles(to 4sf)
now, if 2 moles of magnesium give -1204kJ
How much energy is given by 0.1479 moles
= (0.1479×-1204kJ)
=-89.0358kJ (don't forget the negative sign)
c) two molesof MgO produces -1204kJ of energy
then -234kJ will be produced by
=(-234kJ×2moles)/1204kJ
=0.3887moles
one mole of MgO weighs 24+16=40
therefore the mass produced is 0.3887moles×40=15.548grams
(d) we first find the number of moles of MgO in 40.3 grams
number of moles=mass/RFM
=40.3g/40= 1.0075moles
if 2 moles of MgO give 1204 kJ then decomposing 1.0075 moles requires
(1.0075 moles×1204kJ)/2=606.515kJ
The answer is 20N as when the object is accelerating at 3 m/s2 it as a force of 10N applied to it so to get to 6m/s2 3(x2) = 6 so 10(x2) = 20
Answer:
The masses of the reactants and products are equal.
Explanation:
Hope this helps.