Answer:
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Explanation:
Hello there!
In this case, according to the rules for the oxidation states in chemical reactions, it is possible to realize that lone elements have 0 and since magnesium is in group 2A, it forms the cation Mg⁺² as it loses electrons and oxygen is in group 6A so it forms the anion O⁻²; therefore resulting oxidation numbers are:
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Answer:
1.07 g Ba
Explanation:
Hello there!
In this case, according to the definition of the Avogadro's number and the molar mass, it is possible to say that 6.022x10^{23} atoms of barium equal one mole, and at the same time, 1 mole equals 137.327 grams of this element; thus, it is possible to say that 6.022x10^{23} atoms of barium have a mass of 137.327 grams; therefore, it i possible for us to calculate the required mass in grams as shown below:

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The answer is letter (B).
Answer:
A) Separating funnel method
B) Simple Distillation
C) Evaporation
D) Sublimation
E) It is based on the principle of separation whereby even though two substances are dissolved in the same solvent, their respective solubilities could be different. Thus, the component that has more solubility will rise fastest and will therefore get separated from the mixture.
Explanation:
A)
B) Kerosene and petrol are both miscible liquids and the difference in their boiling point temperature is not more than 25°C. Thus, we make use of Simple distillation.
C) Can be separated by evaporation where the water is boiled and it evaporates and leaves the salt behind
D) To separate camphor from salt, we use sublimation so the camphor can change directly from solid to the gas state without passing through the liquid state.
E) Chromatography is used to separate components of a mixture.
It is based on the principle of separation whereby even though two substances are dissolved in the same solvent, their respective solubilities could be different. Thus, the component that has more solubility will rise fastest and will therefore get separated from the mixture.
Molarity= (number of moles of that substance) / (Volume of solution in litres)
7= (number of moles of HCl) / 0.05
Thus,
Number of moles of HCl = 7 x 0.05 = 0.35
The number of moles of HCl will remain unchanged.
Now, for new solution,
0.35= 0.35 / (New volume of solution in litres)
Thus,
New volume = 1 litre
Thus, amount of water added = 1- 0.05 litre = 5.0 M