Answer:
8.58 g/cm3
Explanation:
density = mass / volume
be attention that the question gives u the length of
one side of the cube so u should calculate the volume
of the cube using your information of math .
1st we calculate the volume of the cube :
V of cube = a 3= axaxa
= 0.250 x0.250 x0.250
= 0.0156 cm3
2nd step
density = mass/volume
= 0.134/ 0.0156 = 8.58 g/cm3
Fixed vs Variable Oxidation is given below.
Explanation:
1.In its compounds, hydrogen has an oxidation number of +1, except. hydrides where the. oxidation number of hydrogen is -1. In their compounds, the metals with fixed oxidation states have the oxidation number that. corresponds with the fixed oxidation number.
A variable oxidation state is a value that determines the charge of the atom depending on certain conditions.
2. Oxidation state of elements is considered to be of the most important in the study of chemistry. For some elements, this figure is constant known as fixed oxidation , while for others it is variable is called variable oxidation state.
3. MgCl2 : magnesium is in Group IIA and all elements in Group IIA have fixed oxidation numbers of +2
FeCl2 : iron has a variable oxidation number of either +2 or +3 and is not fixed
Answer:
The combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy
Explanation:
Given;
CH₄ + 2O₂ → CO₂ + 2H₂O, ΔH = -890 kJ/mol
From the combustion reaction above, it can be observed that;
1 mole of methane (CH₄) released 890 kilojoules of energy.
Now, we convert 59.7 grams of methane to moles
CH₄ = 12 + (1x4) = 16 g/mol
59.7 g of CH₄ 
1 mole of methane (CH₄) released 890 kilojoules of energy
3.73125 moles of methane (CH₄) will release ?
= 3.73125 moles x -890 kJ/mol
= -3320.81 kJ
Therefore, the combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy
The greenhouse effect is when Earth's atmosphere gets surrounded with gasses causing the Earth to warm up.
