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4 years ago

How many molecules are there in 840 grams of na2SO4

Chemistry

1 answer:

beks73 [17]4 years ago

4 0

Answer:

3.56x10^24 molecules

Explanation:

The following data were obtained from the question:

Mass of Na2SO4 = 840g

Molar Mass of Na2SO4 = (23 x2) + 32 + (16x4) =46 + 12 + 64 = 142g/mol

From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules. This also gives that 1mole of Na2SO4 contains 6.02x10^23 molecules.

If 1 mole (i.e 142g) contains 6.02x10^23 molecules,

Therefore, 840g of Na2SO4 will contain = (840 x 6.02x10^23)/142 = 3.56x10^24 molecules

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Andru [333]

Conversating and conversate are actual words

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4 years ago

How many molecules of CaCi2 are equivalent to 75.9 grams

horsena [70]

<em>M CaCl₂: 40+(35,5×2) = 111 g/mol</em>

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X molecules --------------------- 75,9g
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3 years ago

A plant fertilizer contains 15% by mass nitrogen (N). In a container of soluble plant food, there are 12.2 oz of fertilizer. How

ale4655 [162]

51.86 grams would be in the container.

One ounce is an equivalent of 28.34 grams, so times that by 12.2
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3 years ago

Read 2 more answers

Are these synthesis decomposition single replacement or double replacement?

marishachu [46]

Answer:

1. Synthesis

2. Decomposition

3. Single replacement

4. Synthesis

5. Decomposition

6. Synthesis

Explanation:

Kind of a hard picture to look at but let me define each chemical reaction:

Synthesis:

a + b ---> ab In synthesis elements/compounds come together to form new compounds

Decomposition:

ab ---> a + b In decomposition a compound breaks down to form 2 elements/compounds

Single replacement:

a + bc ---> b + ac In a single replacement one element/compound takes the place of another element/compound.

Double replacement

ab + cd ---> ad + bc In a double replacement 2 compounds exchange different elements/compounds.

Now, let's go through the assignment

1. P + O2 --> P4O10 This is a synthesis reaction because the two elements (P and O) came together to form one compound.

2. HgO ---> Hg + O2 This is a decomposition reaction because HgO broke into separate elements Hg and O.

3. Cl2 + NaBr ---> NaCl + Br2 This is a single replacement reaction because chlorine (Cl) replaced the spot of bromine (Br) to bond with sodium (Na).

4. Mg + O2 ---> MgO This is a synthesis reaction because two elements (Mg and O) came together to form one compound.

5. Al2O3 ---> Al + O2 This is a decomposition reactions because Al2O3 broke into separate elements Al and O.

6. H2 + N2 ---> NH3 This is a synthesis reaction because two elements (H and N) came together to form one compound.

<em>I hope this helps!!</em>

7 0

3 years ago

A 25.00 ml solution of sulfuric acid H2SO4 is titrated to phenolphthalein end point with 27.00 ml of 1.700 M KOH

Nastasia [14]

<h3>Answer:</h3>

0.918 M

<h3>Explanation:</h3>

Assuming the question requires we calculate the Molarity of sulfuric acid:

We are given:

Volume of the acid, H₂SO₄ = 25.00 ml
Volume of the base, KOH = 27.00 mL
Molarity of the base, KOH is 1.70 M

We can calculate the molarity of the acid using the following steps;

<h3>Step 1: Write the chemical equation for the reaction.</h3>

The reaction is an example of a neutralization reaction where a base reacts with an acid to form salt and water.

Therefore, the balanced equation will be;

H₂SO₄(aq) + 2KOH(aq) → K₂SO₄(aq) + 2H₂O(l)

<h3>Step 2: Determine the moles of the base, KOH </h3>

When given molarity and the volume of a solution, the number of moles can be calculated by multiplying molarity with volume.

Number of moles = Molarity × Volume

= 1.700 M × 0.027 L

= 0.0459 moles

Thus, moles of KOH used is 0.0459 moles

<h3>Step 3: Determine the number of moles of the Acid, H₂SO₄</h3>

From the reaction, 1 mole of the acid reacts with 2 moles of KOH

Therefore, the mole ratio of H₂SO₄ to KOH is 1 : 2

Thus, moles of H₂SO₄ = Moles of KOH ÷ 2

= 0.0459 moles ÷ 2

= 0.02295 moles

<h3>Step 4: Calculate the molarity of the Acid </h3>

Molarity is the concentration of a solution in moles per liter

Molarity = Moles ÷ Volume

Molarity of the acid = 0.02295 moles ÷ 0.025 L

= 0.918 M

Thus, the molarity of the acid, H₂SO₄ is 0.918 M

5 0

3 years ago