Answer:
Chemical change
Explanation:
From all indicators, Aurelia is seeing a chemical change occurring in the reaction here.
A chemical change is a change in which new substances are produced. For every chemical change:
- they are not easily reversible
- they lead to production of new kinds of substances
- involves mass change
- require considerable amount of energy.
We start off and end with:
Metal + Acid → Black metal + rising gaseous bubbles
Clearly, it is shown that new products are formed and this reaction is impossible to reverse in order to get the reactants back.
This is a typical chemical change.
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>
A.S OLOS kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkll
The answer is developer .
Chloe wants to lighten the color of her dark hair, which will require the use of both hair color and hydrogen peroxide.
Hydrogen peroxide (H₂O₂) is an example of a most commonly used developer in hair color.
Hydrogen peroxide lighten hair color, as it can dissolve darker pigment. According to the natural hair color and the length of time a person will leave hydrogen peroxide on hair, hair can turn somewhere on the color spectrum between caramel, orange and yellow.
g = 19.6 N/2.2 kg. g = 8.9 m/s2. 7.
