All categories

3 years ago

Which statement describes how chemical formulas, such as H2O, represent compounds

Chemistry

2 answers:

grandymaker [24]3 years ago

5 0

Answer:

Which statements describe how chemical formulas, such as H2O, represent compounds? ... They show the elements that make up a compound. They show the types of atoms that make up a molecule. They show the number of each type of atom in a molecule.

lions [1.4K]3 years ago

5 0

Answer: B

Explanation:

You might be interested in

An impure sample of table salt that weighed 0.8421 g, when dissolved in water and treated with excess AgNO3, formed 2.044 g of A

Lilit [14]

Answer:

99.24%.

Explanation:

NaCl reacted with AgNO₃ as in the balanced equation:

NaCl + AgNO₃ → AgCl(↓) + NaNO₃,

1.0 mol of NaCl reacts with 1.0 mol of AgNO₃ to produce 1.0 mol of AgCl and 1.0 mol of NaNO₃.

We need to calculate the no. of moles of AgCl produced:

no. of moles of AgCl = mass/molar mass = (2.044 g)/(143.32 g/mol) = 0.0143 mol.

Now, we can calculate the no. of moles of NaCl that can precipitated as AgCl (0.0143 mol), these moles represents the no. of moles of pure NaCl in the sample:

using cross multiplication:

1.0 mol of NaCl produce → 1.0 mol of AgCl, from the stichiometry.

∴ 0.0143 mol of NaCl produce → 0.0143 mol of AgCl.

Now, we can get the mass of puree NaCl in the sample:

mass of pure NaCl = (no. of moles of pure NaCl)(molar mass of NaCl) = (0.0143 mol)(58.44 g/mol) = 0.8357 g.

∴ The percentage of NaCl in the impure sample = [(mass of pure NaCl)/(mass of the impure sample)] x 100 = [(0.8357 g)/(0.8421 g)] x 100 = 99.24%.

4 0

3 years ago

When hydrogen sulfide gas is bubbled into a solution of sodium hydroxide, the reaction forms sodium sulfide and water. How many

Mumz [18]

Answer:

1.61 g Na₂S

Explanation:

To find the mass of sodium sulfide (Na₂S) generated from hydrogen sulfide (H₂S) and sodium hydroxide (NaOH), you need to (1) construct the balanced chemical equation, then (2) calculate the molar masses of each molecule involved, then (3) convert grams of each reagent to grams of the product (via the molar masses and mole-to-mole ratio from equation coefficients), and then (4) determine the limiting reagent and final answer. It is important to arrange the conversions in a way that allows for the cancellation of units (the desired unit should be in the numerator).

(Step 1)

The unbalanced equation:

H₂S + NaOH ---> Na₂S + H₂O

Reactants: 3 hydrogen, 1 sulfur, 1 sodium, 1 oxygen

Products: 2 hydrogen, 1 sulfur, 2 sodium, 1 oxygen

The balanced equation:

H₂S + 2 NaOH ---> Na₂S + 2 H₂O

Reactants: 4 hydrogen, 1 sulfur, 2 sodium 2 oxygen

Products: 4 hydrogen, 1 sulfur, 2 sodium, 4 oxygen

(Step 2)

Molar Mass (H₂S): 2(1.008 g/mol) + 32.065 g/mol

Molar Mass (H₂S): 34.081 g/mol

Molar Mass (NaOH): 22.990 g/mol + 15.998 g/mol + 1.008 g/mol

Molar Mass (NaOH): 39.998 g/mol

Molar Mass (Na₂S): 2(22.990 g/mol) + 32.065 g/mol

Molar Mass (Na₂S): 78.045 g/mol

(Step 3)

1.50 g H₂S 1 mole 1 mole Na₂S 78.045 g
----------------- x ---------------- x -------------------- x ----------------- =
34.081 g 1 mole H₂S 1 mole

= 3.43 g Na₂S

1.65 g NaOH 1 mole 1 mole Na₂S 78.045 g
-------------------- x ---------------- x ----------------------- x ---------------- =
39.998 g 2 moles NaOH 1 mole

= 1.61 g Na₂S

(Step 4)

Because NaOH generates less product, it will run out before all of the H₂S is used. This makes NaOH the limiting reagent and the final answer 1.61 grams Na₂S.

5 0

1 year ago

What is baking soda chemically known as ? Excessive use of chemical

andreyandreev [35.5K]

Answer:

Baking Soda is NaHCO3 ---Sodium hydrogen Carbonate

Excessive use of Fertilizer can cause plants to develop shallow root systems,Decrease soil fertility and reduce Quality of Crops.

7 0

3 years ago

Read 2 more answers

I need help pls Where does it belong to?

Daniel [21]

The answer is B. Fungi,Protists

6 0

2 years ago

Why do we use 51.0mL of NaOH but only 50.0mL of HCl?

bixtya [17]

Answer

Na OH reacts with H Cl and forms Na Cl and H₂O

NaOH + HCl → NaCl + H₂O

Here we can see that 1 mole of NaOH reacting with 1 mole of HCl and forming 1 mole of NaCl and 1 mole of H₂O

when NaOH and HCl are added together in equal amount then they will completely neutralize each other but NaOH is hygroscopic in nature which means it can absorb water from air so it will not be weighted accurately.

hence, for neutralization we will take extra NaOH.

3 0

3 years ago