A rock weighing 26.0 g is placed in in a graduated cylinder displacing the volume from 13.2mL to 25.3 mL. What is the density of
2 answers:
Answer : The density of the rock is,
Explanation : Given,
Mass of the rock = 26 g
Initial volume = 13.2 ml
Increased volume = 25.3 ml
First we have to calculate the volume of the rock.
Volume of rock = Increased volume of water - Initial volume of water
Volume of rock = 25.3 ml - 13.2 ml = 12.1 ml
Now we have to calculate the density of rock.
Formula used :
Now put all the given values in this formula, we get the density of the rock.
Conversion :
Therefore, the density of the rock is,
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Let the three equations with given be denoted as (1), (2), (3), and the last equation (4). Let
,
, and
be letters such that
. This relationship shall hold for all chemicals involved.
There are three unknowns; it would thus take at least three equations to find their values. Species present on both sides of the equation would cancel out. Thus, let coefficients on the reactant side be positive and those on the product side be negative, such that duplicates would cancel out arithmetically. For instance, shall resemble the number of
left on the product side when the second equation is directly added to the third. Similarly
:
:
:
Thus
and
Verify this conclusion against a fourth species involved- for instance. Nitrogen isn't present in the net equation. The sum of its coefficient shall, therefore, be zero.
Apply the Hess's Law based on the coefficients to find the enthalpy change of the last equation.