Answer:In a physical change, atoms are not rearranged and the matter's physical and chemical properties are unchanged. Chemical changes, on the other hand, rearrange the atoms of matter in new combinations, resulting in matter with new physical and chemical properties.
Explanation:
easy
Answer: 30.978
Explanation:
From the equation 2 moles of Fe will result in 3 moles copper
so .325 moles Fe will result in .4875 moles Cu
Cu weights 63.546 gm per mole
.4875 moles * 63.546 gm / mole = 30.978 gm of Cu
Answer:
The environment Ecosystems are also affected by climate change. Habitats are being modified, the timing of events such as flowering and egg laying are shifting, and species are altering their home ranges. Changes are also occurring to the ocean.
Explanation:
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Answer:</h3>
b. 1 Potassium atom
c. 1 bromine atom
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Explanation:</h3>
What is a compound?
- A compound is a substance that is made up of atoms from different elements.
- The formula of a compound shows the elements making up the compound.
- Additionally, the formula of compound shows the number atoms of each element making up the compound.
In this case;
We are given the Formula KBr
- This is the formula of the compound potassium bromide.
- From the formula, we can tell that the compound is made up of potassium and bromine atoms.
- The formula also shows the number of atoms of each element, that is, 1 potassium atom and 1 bromide atom.
Answer:
(D) Na₂SO₄•10H₂O (M = 286).
Explanation:
- The depression in freezing point of water by adding a solute is determined using the relation:
<em>ΔTf = i.Kf.m,</em>
Where, ΔTf is the depression in freezing point of water.
i is van't Hoff factor.
Kf is the molal depression constant.
m is the molality of the solute.
- Since, Kf and m is constant for all the mentioned salts. So, the depression in freezing point depends strongly on the van't Hoff factor (i).
- van't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass.
(A) CuSO₄•5H₂O:
CuSO₄ is dissociated to Cu⁺² and SO₄²⁻.
So, i = dissociated ions/no. of particles = 2/1 = 2.
B) NiSO₄•6H₂O:
NiSO₄ is dissociated to Ni⁺² and SO₄²⁻.
So, i = dissociated ions/no. of particles = 2/1 = 2.
(C) MgSO₄•7H₂O:
MgSO₄ is dissociated to Mg⁺² and SO₄²⁻.
So, i = dissociated ions/no. of particles = 2/1 = 2.
(D) Na₂SO₄•10H₂O:
Na₂SO₄ is dissociated to 2 Na⁺ and SO₄²⁻.
So, i = dissociated ions/no. of particles = 3/1 = 3.
∴ The salt with the high (i) value is Na₂SO₄•10H₂O.
So, the highest ΔTf resulted by adding Na₂SO₄•10H₂O salt.