Answer:
Option D:
evaporation from lakes and rivers
Explanation:
The water cycle is a natural cycle that shows how water moves and circulates within a natural environment. Water usually moves between the hydrosphere and the atmosphere through evaporation and condensation.
When water evaporates from the hydrosphere (the water bodies), it goes up into the atmosphere where it cools to become clouds. As more water evaporates, the clouds formed increase in mass. Once the clouds are too heavy to be held up in the sky, they fall down as precipitation (rain, snow, hail) into the water bodies and surrounding land below.
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>
Answer:
28g
Solution. Hence, 2 moles of nitrogen atoms weigh 28g.
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
