Answer:
I think third C12/hv is right answer
2.48 grams.
<h3>Explanation</h3>
Start by finding the formula mass for cobalt (II) chloride and cobalt (II) chloride hexahydrate.
As a transition element in the middle d-block of the periodic table, cobalt can form ions with a plurality of charges. It is thus necessary to indicate its charge in systematic names of cobalt-containing formula.
The cation "cobalt" in the systematic name of the salt has the Roman numeral "(II)" attached to it in brackets. As a metal, cobalt forms positively-charged ion. The one here thu has charge of +2.
Chloride ions have charges -1. Charges cancel out to produce neutral compounds. Each cobalt cation in this salt would thus pair with two chloride anions. Hence the empirical formula: .
The prefix "<em>hexa-</em>" in the name cobalt (II) chloride <em>hexa</em>hydrate indicates that every formula unit of this salt contains six units of water. The hydrated salt thus has an empirical formula of .
Given the relative atomic mass for each of the elements, as seen on a modern periodic table of the elements:
- Cobalt- 58.93
- Chloride- 35.45
- Hydrogen- 1.008
- Oxygen- 16.00
Thus the formula mass of each compound
- Cobalt (II) chloride - 129.83
- Cobalt (II) chloride hexahydrate - 262.12
Cobalt (II) chloride hexahydrate decomposes under heat to produce cobalt (II) hexahydrate and water. Hence the equation:
Therefore
- Molar ratio:
- Mass ratio:
The mass ratio indicates that 262.12 grams of cobalt (II) chloride hexahydrate decomposes to produce 129.83 grams of its corresponding anhydrous salt. Accordingly, heating 5.00 grams of the hexahydrate would produce 2.48 grams of its anhydrate.
Answer:
The answer is forensic sociologist
I just took the exam and it’s rights
Answer:0.178 moles
Explanation: carbon trihydride seems to be an unusual name for the methyl group CH3–
ionic wt 15
moles = 2.67/15 = 0.178
Answer:
174.8 g/m is the molar mass of the solute
Explanation:
We must apply colligative property of freezing point depression.
ΔT = Kf . m . i
ΔT = T° freezing pure solvent - T° freezing solution (0° - (-2.34°C) = 2.34°C
Kf = Fussion constant for water, 1.86 °C/m
As ascorbic acid is an organic compound, we assume that is non electrolytic, so i = 1
2.34°C = 1.86°C/m . m
2.34°C / 1.86 m/°C = 1.26 m
This value means the moles of vitamin C, in 1000 g of solvent
We weighed the solute in 250 g of solvent, so let's calculate the moles of vitamin C.
1000 g ___ 1.26 moles
In 250 g ___ (250 . 1.26)/1000 = 0.314 moles
This are the moles of 55 g of ascorbic acid, so the molar mass, will be:
grams / mol ⇒ 55 g/0.314 m = 174.8 g/m