Delta Hf = dHf
<span>dHf rxn = (n*dHf products) - (n*dHf reactants). </span>
<span>Substitute 5113.3 kJ for dHf rxn and solve for the only unknown in the equation which is dHf C8H18.
</span>-5133.3-[(8x-393.5)+9(-241.8)] = 190.9
<span>Since it is an enthalpy of formation, the value has to be negative, </span>
<span>thus the correct answer is -190.9</span>
Answer:
There are 6.022×1023 molecules in a mole. There are 18.01528 grams of water per mole of water. in 1g water
Explanation:
please Mark my answer in brainlist
Answer : The speed in miles per hour is 22 mile/hr.
The speed in yard per min is 26617.8 yard/min
Explanation :
The conversion used for meters to miles is:

The conversion used for second to hour is:

The conversion used for meter per second to mile per hour is:

As we are given the speed of 407.0 meter per second. Now we have to determine the speed in miles per hour.

So, 
Therefore, the speed in miles per hour is 22 mile/hr.
The conversion used for meter to yard
1m = 1.09 yard
The conversion used for second to hour is:

The conversion used for meter per second to mile per hour is:


As we are given the speed of 407.0 meter per second. Now we have to determine the speed in yards per min

So, 
Therefore, the speed in yard per min is 26617.8 yard/min
Answer:
the sun is the smallest object in our Solar System
Explanation: