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2 years ago

Jati has a sample of a solid.Suggest how he could find out weather the solid is a pure substance or a mixture of substances?

Chemistry

1 answer:

Vsevolod [243]2 years ago

5 0

Answer:

The melting point range of a substance is the temperature range from which the first crystal starts to melt, to the temperature at which the last crystal finishes melting. An impure substance is a type of mixture, so melting points can be used to find out if a substance is pure or impure.

pls mark brainiest

Explanation:

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Consider the following reaction at 25 °C: 4Fe(s) + 3O2(g) ⇌ 2Fe2O3(s) An equilibrium mixture contains 1.0 mol Fe, 1.0 × 10–3 mol

tino4ka555 [31]

Answer:

Kc = Kc = 8.0 * 10^9

Kp = 5.5 *10^5

Explanation:

Step 1: Data given

Temperature = 25.0 °C

Number of moles Fe = 1.0 moles

Number of moles O2 = 1.0 * 10^-3 moles

Number of moles Fe2O3 = 2.0 moles

Volume = 2.0 L

Step 2: The balanced equation

4Fe(s) + 3O2(g) ⇌ 2Fe2O3(s)

Step 3: Calculate molarity

Molarity = moles / volume

[Fe] = 1.0 moles / 2.0 L

[Fe] = 0.5 M

[O2] = 0.001 moles / 2.0 L

[O2] = 0.0005 M

[Fe2O3] = 2.0 moles / 2.0 L

[Fe2O3] = 1.0 M

Step 4: Calculate Kc

Kc =1/ [O2]³

Kc = 1/0,.000000000125

Kc = 8.0 * 10^9

Step 5: Calculate Kp

Kp = Kc*(R*T)^Δn

⇒with Kc = 8.0*10^9

⇒with R = 0.08206 L*atm /mol*K

⇒with T = 298 K

⇒with Δn = -3

Kp = 8.10^9 *(0.08206 * 298)^-3

Kp = 5.5 *10^5

4 0

2 years ago

assuming the magnesium ribbon wasn't sufficiently polished to remove a coating of magnesium oxie on the surface. how would this

Ira Lisetskai [31]

The magnesium ribbon wasn't sufficiently polished to remove a coating of magnesium oxie on the surface. how would this affect the volume of hydrogen gas produced? would this error cause the gas constant to be overestimated, underestimated, or remain unaffected?

1. Since, the magnesium ribbon wasn’t sufficiently polished to remove a coating of magnesium oxide on surface, the actual mass of magnesium taken will be less (as it also contains magnesium oxide). Hence, the number of moles of magnesium reacted and the number of moles of hydrogen produced will be less. Due to this, the volume of hydrogen gas produced will be less and the gas constant will be underestimated. R=\frac {PV}{nT} . Here n is calculated from weight of Mg taken but V is measured. Thus values of n will be same but the value of V will be lower. Hence, the value of R will be lower.

2. When droplets of water are remaining in the eudiometer tube, there volume will be added to the volume of hydrogen and the measured volume of hydrogen will be more than actual volume. Due to this, the value of the gas constant will be overestimated.

3. When small amount of hydrogen dissolves in water, the measured volume of hydrogen will be lower than the actual volume. This will underestimate the value of the gas constant.

4. When the temperature of the gas was underestimated, the value of the gas constant will be overestimated as the gas constant is inversely proportional to the temperature. {PV}

{nT}.

Magnesium is a chemical detail with the symbol Mg and atomic number 12. it is a glittery gray solid which stocks many bodily and chemical residences with the alternative 5 alkaline earth metals (institution 2 of the periodic desk).

This element is produced in huge, growing old stars from the sequential addition of three helium nuclei to a carbon nucleus. whilst such stars explode as supernovas, a lot of the magnesium is expelled into the interstellar medium wherein it may recycle into new big name structures. Magnesium is the eighth maximum abundant element inside the Earth's crust and the fourth maximum not unusual detail in the Earth (after iron, oxygen and silicon), making up 13% of the planet's mass and a big fraction of the planet's mantle. it's miles the 0.33 maximum abundant detail dissolved in seawater, after sodium and chlorine.

Learn more about Magnesium here:-brainly.com/question/25860912

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8 0

1 year ago

How many molecules are in 1.2 moles of H20?

Otrada [13]

<h3>Answer:</h3>

7.226 × 10^23 molecules.

<h3>Explanation:</h3>

A compound is a substance that is made by two or more atoms from different elements.

A mole of a compound contains a number of molecules equivalent to Avogadro's number, 6.022 × 10^23.
That is, one mole of a compound contains 6.022 × 10^23 molecules.

In this case we are given;

Number of moles of H₂O as 1.2 moles

But, 1 mole of H₂O contains 6.022 × 10^23 molecules.

We are required to calculate the number of molecules present;

To calculate the number of molecules we are going to multiply the number of molecules in one mole by the number of moles.

Therefore;

Number of molecules = 1.2 moles × 6.022 × 10^23 molecules/mole

= 7.226 × 10^23 molecules.

Thus, 1.2 moles of water contains 7.226 × 10^23 molecules.

4 0

3 years ago

HELP WILL GIVE BRAINLIEST

DaniilM [7]

The presence of enzymes

7 0

3 years ago

Read 2 more answers

Which element would you expect to be more metallic?<br> (a) S or Cl (b) In or Al (c) As or Br

Natalija [7]

Explanation:

When we move across a period from left to right then there will occur an increase in electronegativity and also there will occur an increase in non-metallic character of the elements.

As sulfur (S) is a group 16 element and chlorine (Cl) is a group 17 element. Hence, sulfur (S) is more metallic in nature than chlorine.

This means that chlorine (S) is less metallic than chlorine (Cl).

Both indium (I) and aluminium (Al) are group 13 elements. And, when we move down a group then there occur an increase in non-metallic character of the elements. As indium belongs to group 13 and period 5 whereas aluminium belongs to group 13 and period 3.

Therefore, aluminium (Al) is more metallic than indium (In).

Arsenic (Ar) is a group 15 element and bromine (Br) is a group 17 element. Therefore, arsenic is more metallic than bromine.

4 0

3 years ago