Answer:
Molecular formulas describe the exact number and type of atoms in a single molecule of a compound. The constituent elements are represented by their chemical symbols, and the number of atoms of each element present in each molecule is shown as a subscript following that element's symbol.
The temperature of the countertop changes by 0.032 °C
The quantity of heat transferred to the countertop is given by
Q = CΔT where Q = quantity of heat transferred to the countertop = 5000 J = 5 kJ, C = heat capacity of the countertop = 158.5 kJ/°C and ΔT = temperature change of the countertop.
Since we require the temperature change of the countertop, we make ΔT subject of the formula.
So, ΔT = Q/C
So, substituting the values of the variables into the equation, we have
ΔT = Q/C
ΔT = 5 kJ/158.5 kJ/°C
ΔT = 0.032 °C
So, the temperature of the countertop changes by 0.032 °C
Learn more about temperature change here:
brainly.com/question/16384350
We are given that the balanced chemical reaction is:
cacl2⋅2h2o(aq) +
k2c2o4⋅h2o(aq) --->
cac2o4⋅h2o(s) +
2kcl(aq) + 2h2o(l)
We known that
the product was oven dried, therefore the mass of 0.333 g pertains only to that
of the substance cac2o4⋅h2o(s). So what we will do first is to convert this
into moles by dividing the mass with the molar mass. The molar mass of cac2o4⋅h2o(s) is
molar mass of cac2o4 plus the
molar mass of h2o.
molar mass cac2o4⋅h2o(s) = 128.10
+ 18 = 146.10 g /mole
moles cac2o4⋅h2o(s) =
0.333 / 146.10 = 2.28 x 10^-3 moles
Looking at
the balanced chemical reaction, the ratio of cac2o4⋅h2o(s) and k2c2o4⋅h2o(aq) is
1:1, therefore:
moles k2c2o4⋅h2o(aq) = 2.28
x 10^-3 moles
Converting
this to mass:
mass k2c2o4⋅h2o(aq) = 2.28
x 10^-3 moles (184.24 g /mol) = 0.419931006 g
Therefore:
The mass of k2c2o4⋅<span>h2o(aq) in
the salt mixture is about 0.420 g</span>
<span>(0.1875 moles)(98.004 g/mole) = 18.37575 g </span>
<span>In correct number of significant figures: 18.4 </span>
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