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2 years ago

PLS HELP!!!!

Chemistry

2 answers:

Mashcka [7]2 years ago

7 0

Answer:

the 3rd answer

White raven [17]2 years ago

4 0

How do the products of chemical reactions compare to their reactants?

Answer:

The products often have completely different properties than the reactants.

You might be interested in

Calculate the molarity of the two solutions.

beks73 [17]

Answer:

A = Molarity = 0.22 M

B = Molarity = 0.36 M

Explanation:

Given data:

For first solution:

number of moles = 0.550 mol

Volume of solution = 2.50 L

Molarity = ?

Molarity:

Formula:

Molarity = number of moles of solute / volume of solution in L.

Molarity = 0.550 mol / 2.50 L

Molarity = 0.22 M

For second solution:

Mass of NaCl = 15.7 g

Volume of solution = 709 mL or 709/1000 = 0.709 L

Molarity = ?

Solution:

Number of moles = mass / molar mass

Number of moles = 14.7 g/ 58.44 g/mol

Number of moles = 0.252 mol

Molarity:

Molarity = number of moles of solute / volume of solution in L.

Molarity = 0.252 mol / 0.709 L

Molarity = 0.36 M

8 0

3 years ago

A chemistry student needs to standardize a fresh solution of sodium hydroxide. She carefully weighs out 385.mg of oxalic acid H2

Vlada [557]

Answer:

The molarity of the sodium hydroxide solution is 0.0692 M

Explanation:

Step 1: Data given

Mass of H2C2O4 = 385 mg = 0.385 grams

volume = 250 mL = 0.250 L

Volume of NaOH = 123.7 mL = 0.1237 L

Molar mass H2C2O4 = 90.03 g/mol

Step 2: The balanced equation

2NaOH + H2C2O4 → Na2C2O4 + 2H2O

Step 3: Calculate moles H2C2O4

Moles H2C2O4 = mass H2C2O4 / molar mass H2C2O4

Moles H2C2O4 = 0.385 grams / 90.03 g/mol

Moles H2C2O4 = 0.00428 moles

Step 4: Calculate molarity of H2C2O4

Molarity H2C2O4 = moles / volume

Molarity H2C2O4 = 0.00428 moles / 0.250 L

Molarity H2C2O4 = 0.01712 M

Step 5: Calculate molarity of NaOH

2*Ca*Va = n*Cb*Vb

⇒ with Ca = Molarity of H2C2O4 = 0.01712 M

⇒ Va = volume of H2C2O4 = 0.250 L

⇒Cb = molarity of NaOH = TO BE DETERMINED

⇒ Vb = volume of NaOH = 0.1237 L

Cb = (2*0.01712*0.250)/0.1237

Cb = 0.0691 M

The molarity of the sodium hydroxide solution is 0.0692 M

4 0

3 years ago

Which states of matter only appear in the hydrosphere

Oliga [24]

I would say the answer is liquids

7 0

2 years ago

Which of the following is a limitation of Bohr's model?

Murljashka [212]

Answer:

The answer is:

The first option

Explanation:

6 0

2 years ago

Sodium metal and water react to create sodium hydrogen and hydrogen gas through the unbalanced equation.

Maurinko [17]

Answer:

Theoretical yield = 2.5 g

Explanation:

Given data:

Mass of sodium = 79.7 g

Mass of water = 45.3 g

Theoretical yield of hydrogen gas = ?

Solution:

Chemical equation:

2Na + 2H₂O → 2NaOH + H₂

Number of moles of sodium:

Number of moles = mass/ molar mass

Number of moles = 79.7 g / 23 g/mol

Number of moles = 3.5 mol

Number of moles of water:

Number of moles = mass/ molar mass

Number of moles = 45.3 g / 18g/mol

Number of moles = 2.5 mol

Now we will compare the moles of hydrogen gas with water and sodium.

H₂O : H₂

2 : 1

2.5 : 1/2×2.5 =1.25 mol

Na : H₂

2 : 1

3.5 : 1/2×3.5 =1.75 mol

water will be limiting reactant.

Theoretical yield:

Mass = number of moles × molar mass

Mass = 1.25 mol × 2 g/mol

Mass = 2.5 g

8 0

2 years ago