Answer : The correct option is, (D) 3600 kJ
Explanation :
Mass of octane = 75 g
Molar mass of octane = 114.23 g/mole
Enthalpy of combustion = -5500 kJ/mol
First we have to calculate the moles of octane.

Now we have to calculate the heat released in the reaction.
As, 1 mole of octane released heat = -5500 kJ
So, 0.656 mole of octane released heat = 0.656 × (-5500 kJ)
= -3608 kJ
≈ -3600 kJ
Therefore, the heat released in the reaction is 3600 kJ
Answer:
2.318032g
Explanation:
-The electrolysis equation of water is written as below:

-The mole ratio of Water to the hydrogen formed is 1:1, therefore 2.3 moles of hydrogen gas is produced.
-Hydrogen's molar mass is 1.00784 grams:

Hence, 2.318032 grams of hydrogen is produced.
Answer:
helium hydrogen
Explanation:
lithium beryllium bottom carbon
Answer:
Volume
Explanation:
Density:
Density is equal to the mass of substance divided by its volume. In order to find the density of earth when mass is given we have to calculate its volume. The volume of earth is calculated by using the volume formula for sphere. i.e 4/3 π r³. we also require radius to find the volume and we know that
Diameter = 2 × radius
The diameter of earth equator is 12756.75 Km. So we calculate the radius by dividing the diameter by 2. Then by putting the value of radius in 4/3 π r³ we will get the volume and then we can calculate the density of earth.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
Symbol:
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
Answer:
An atom gets larger as the number of electronic shells increase; therefore the radius of atoms increases as you go down a certain group in the periodic table of elements. In general, the size of an atom will decrease as you move from left to the right of a certain period.
Explanation: