Write a hypothesis that answers the lesson

Methyl bromide (CH3Br) a. is extremely flammable b. is of greater concern from its oral toxicity than from its inhalation toxici

Mekhanik [1.2K]

Answer:

I believe it is C.

Explanation:

Hope my answer has helped you and if not i'm sorry.

4 0

3 years ago

A solution of phosphoric acid was made by dissolving 10.0 g of H3PO4 in 100.0 mL of water. The resulting volume was 113 mL. Calc

rodikova [14]

Explanation:

Mass of solute = 10.0 g

mass of solvent(water) = m

Volume of solvent( water) = v = 100.0 mL

Density of water= d = $1 g/cm^3=1 g/mL$

$1 mL= 1 cm^3$

$m=d\times v=1.0 g/mL\times 100.0 = 100.0 g$

Mass of solution(M) = Mass of solute + mass of solvent

M = 10.0 g + 100.0 g = 110.0 g

Volume of the solution = V = 113 mL

Density of the solution = D

$D=\frac{M}{V}=\frac{110.0 g}{113 mL}=0.9734 g/mL$

The density of the solution is 0.9734 g/ml.

Moles of phosphoric acid = $n_1=\frac{10.0 g}{98 g/mol}=0.1020 mol$

Moles of water = $n_2=\frac{100.0 g}{18g/mol}=5.556 mol$

Mole fraction of phosphoric acid = $\chi_1$

$\chi_1=\frac{n_1}{n_1+n_2}=\frac{0.1020 mol}{0.1020 mol+5.556 mol}$

$\chi_1=0.01803$

Mole fraction of water = $\chi_2$

$\chi_2=\frac{n_2}{n_1+n_2}=\frac{5.556 mol}{0.1020 mol+5.556 mol}$

$\chi_2=0.9820$

$[Molarity]=\frac{\text{Moles of solute}}{\text{Volume of solution(L)}}$

Moles of phosphoric acid = 0.1020 mol

Volume of the solution = V = 113 mL = 0.113 L ( 1 mL = 0.001 L)

Molarity of the solution :

$=\frac{0.1020 mol}{0.113 L}=0.903 M$

$[Molality]=\frac{\text{Moles of solute}}{\text{Mass of solvent(kg)}}$

Moles of phosphoric acid = 0.1020 mol

Mass of solvent(water) = m =100.0 g = 0.100 kg ( 1 g = 0.001 kg)

Molality of the solution :

$=\frac{0.1020 mol}{0.100 kg}=1.02 mol/kg$

6 0

3 years ago

A silver ring reacts with compounds containing sulfur in the air to form silver sulfide, a black substance that makes up the tar

bearhunter [10]

Answer: B

Explaination: The liquid solution changed color means is turned into a different substance with different properties. It is chemical change .

5 0

3 years ago

Read 2 more answers

Which of the following reactions is incorrectly labeled?

mars1129 [50]

Answer:

The option a termed as precipitation reaction is incorrectly labelled. 

Explanation:

The chemical reactions are classified based on the reactants used and products formed in a reaction. They are decomposition reaction, single displacement reaction, double displacement reaction, acid-base neutralisation reaction, precipitation reaction, combustion reaction, redox reaction and organic reaction.

Among these, the given options are labelled as precipitation and combustion reaction. The one which is labelled as combustion reaction is correct because combustion reactions occur in the presence of oxygen only and the products of combustion reaction should include water, oxygen or carbon and heat.

The other option which is labelled as precipitation reaction is incorrect because precipitation reaction occurs when an ionic substance will come out of a solution due to heating it or stirring it making the solubility of the ionic substance in a solution zero such that it will come out as solid and form a layer at the bottom of the solution.

But in this case all the products are in aqueous state, there is absence of any ionic substance in solid state, so the option which is labelled as precipitation reaction is incorrectly labelled.

3 0

3 years ago

Lily is trying to measure the volume of her hand. She places it in a can full of water. The volume of water that is __________ i

PolarNik [594]

Answer:

Displaced

Explanation:

A convenient way to measure the volume of an object is to measure the volume of a solid is to immerse the solid into water.

When a solid is immersed in water, it displaces some volume of water. This volume of water displaced is the same as the volume of the object.

For instance, if the volume of water in a measuring cylinder was 25 ml and i added a stone which made the water in the measuring cylinder to rise to 70 ml, it simply means that the volume of the object is 70 ml - 25 ml = 45 ml

8 0

3 years ago