216 J of energy is required to raise the temperature of a piece of aluminum from 15.0º C to to 35º C.
Calculate the mass of aluminum used.
(Specific heat of aluminum = 0.90 J ∙ º C-1 ∙ g-1)

12g

Explanation:

The amount of energy (Q) required to raise the temperature of a substance depends on its Mass (M), specific heat capacity (C) and change in temperature (Φ)

Thus, Q = MCΦ

Given that:

Q = 216 joules

Mass of aluminium = ? (let unknown value be Z)

C = 0.90 JºC-1g-1

Φ = (Final temperature - Initial temperature)

= 35°C - 15°C = 20°C

Then, Q = MCΦ

216 J = Z x 0.90 JºC-1g-1 x 20°C

216 J = Z x 18 J°g-1

Z = (216J/18 J°g-1)

Z = 12g

Thus, the mass of the aluminium is 12grams

convalent bond :

is a chemical bond formed by the sharing of electron between 2 atoms.

it is the direct chemical bond between 2 atoms.

in bond formation atoms are involved here.

electrovalent bond:

is a chemical bond defined as electroststic attraction between 2 atoms.

it is the electrostatic attraction between 2 atoms.

in bond formation, ions are involved here.

hope it

and ur welcm

: )

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !