Answer:
823.7g
Explanation:
Using the formula as follows:
Q = m × c × ∆T
Where;
Q = amount of heat (J)
m = mass of substance (g)
c = specific heat capacity (J/g°C)
∆T = change in temperature (°C)
Using the information given in this question as follows:
Q = 6,400 J
m = ?
c of soil = 0.840 J/g°C
∆T = 9.25°C
Using Q = mc∆T
m = Q ÷ c∆T
m = 6,400 ÷ (0.840 × 9.25)
m = 6400 ÷ 7.77
m = 823.7g
11. I would say physical because the color of the item is changed and the texture and density is changed aswell.
Answer:
0.02 tons of NO produced when 4 tons of coal is burned
Explanation:
From the given,
Chemical formula of coal = 
Molecular mass of coal = 
Let’s calculate the mass of nitrogen in coal


Amount of coal burnt = 4tons
Amount of NO produced by burning 4tons = 
This nitrogen is converted into NO by reacting with atmospheric oxygen.
In an unknown liquid, the percentage composition with respect to carbon, hydrogen and iodine is 34.31%, 5.28% and 60.41% respectively.
Let the mass of liquid be 100 g thus, mass of carbon, hydrogen and oxygen will be 34.31 g, 5.28 g and 60.41 g respectively.
To calculate molecular formula of compound, convert mass into number of moles as follows:

Molar mass of carbon, hydrogen and iodine is 12 g/mol, 1 g/mol and 126.90 g/mol.
Taking the ratio:

Putting the values,

Thus, molecular formula of compound will be
.
Answer:
The configuration of the atom would be 2-8-2.
Explanation:
Any atom of an element combines with other element to complete its octet and become stable.
The electron configuration of the given atom is 2-8-6. That means the atom has 6 electrons in its outermost shell. To become stable the atom should have 8 electrons in its outermost shell. The given atom has 6 electrons so it either lose 6 electrons or gain 2 electrons to complete its octet.
But we know the atom having 5,6,7 electrons in its outermost shell they do not lose, they gain either 3 or 2 or 1 electrons to complete its octet.
So we say that atom with the electron configuration 2-8-6 bond with the atom having electron configuration 2-8-2.