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3 years ago

How to do q solution, qrxn, moles of Mg , and delta Hrxn?

Chemistry

1 answer:

Helga [31]3 years ago

6 0

Answer:

14, 508J/K

ΔHrxn =q/n

where q = heat absorbed and n = moles

Explanation:

m = mass of substance (g) = 0.1184g

1 mole of Mg - 24g

n moles - 0.1184g

n = 0.0049 moles.

Also, q = m × c × ΔT

Heat Capacity, C of MgCl2 = 71.09 J/(mol K)

∴ specific heat c of MgCL2 = 71.09/0.0049 (from the formula c = C/n)

= 14, 508 J/K/kg

ΔT= (final - initial) temp = 38.3 - 27.2

= 11.1 °C.

mass of MgCl2 = 95.211 × 0.1184 = 11.27

⇒ q = 11.27g × 11.1 °C × 14, 508 j/K/kg

= 1,7117.7472 J °C-1 g-1

∴ ΔHrxn = q/n

=1,7117.7472 ÷ 0.1184

= 14, 508J/K

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How does doubling the volume of solvent affect the concentration of the solution?

Alex17521 [72]

Answer:

Molarity is halved when the volume of solvent is doubled.

Explanation:

Using the dilution equation (volume 1)(molarity 1)=(volume 2)(molarity 2), we can demonstrate the effects of doubling volume.

Suppose the starting volume is 1 L and the starting molarity is 1 M, and doubling the volume would make the final volume 2 L.

Plugging these numbers into the equation, we can figure out the final molarity.

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This shows that the molarity is halved when the volume of solvent is doubled.

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3 years ago

What is the ionic formula of the compound formed by Co3+ and the phosphorus ion? What is the name of the compound formed based o

klasskru [66]

Answer: The ionic formula of compound is $CoP$ and the name is cobalt phosphide.

Explanation:

For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.

Here element Co is having an oxidation state of +3 called as $Co^{3+}$ cation and phosphprous forms $P^{3-}$ anion with oxidation state of -3. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral $CoP$

The nomenclature of ionic compounds is given by:

1. Positive is written first followed by the oxidation state of metal in roman numerals in square brackets.

2. The negative ion is written next and a suffix is added at the end of the negative ion. The suffix written is '-ide'.

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3 years ago

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tensa zangetsu [6.8K]

Calcium bicarbonate - Ca(HCO3)2
sodium peroxide - Na202
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2 years ago

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Sophie [7]

Each section would be 230 centimeters or 2.30 meters long.

<h3>Sectional division</h3>

The original wood pole is 12 meters long.

12 meters = 12 x 100 = 1200 centimeters

It is to be cut into 5 equal sections: 1200/5 = 240 centimeters

But each cut wastes 10 cm of the pole.

240 - 10 = 230 centimeters.

Thus, each section would be 230 centimeters or 2.30 meters long.

More on sectional divisions can be found here: brainly.com/question/15381501

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2 years ago

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Dmitrij [34]

Answer:

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