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3 years ago

Greg rollerblades 35 meters in 12 seconds. What is his speed?

Chemistry

1 answer:

zheka24 [161]3 years ago

7 0

Answer:

2.916

Explanation:

because the equation for speed is distance divided by time

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What is the atomic number for neon?

Anna35 [415]

Atomic Number for neon is 10

4 0

3 years ago

For the chemical reaction

polet [3.4K]

Answer:

806.3g

Explanation:

Given parameters:

Number of moles of silver nitrate = 4.85mol

Unknown:

Mass of silver chromate = ?

Solution:

2AgNO₃ + Na₂CrO₄ → Ag₂CrO₄ + 2NaNO₃

To solve this problem, we work from the known to the unknown;

The known specie here is AgNO₃ ;

From the balanced chemical equation;

2 moles of AgNO₃ will produce 1 mole of Ag₂CrO₄

4.85 moles of AgNO₃ will produce $\frac{4.85}{2}$ = 2.43moles of Ag₂CrO₄

Mass of silver chromate produced;

mass = number of moles x molar mass

Molar mass of Ag₂CrO₄

Atomic mass of Ag = 107.9g/mol

Cr = 52g/mol

O = 16g/mol

Input the parameters and solve;

Molar mass = 2(107.9) + 52 + 4(16) = 331.8g/mol

So,

Mass of Ag₂CrO₄ = 2.43 x 331.8 = 806.3g

8 0

3 years ago

Which solute would be more effective at lowering the freezing point of water: MgCl2 and KNO3? Explain.

Phantasy [73]

Answer:

AlCl₃.

Explanation:

Adding solute to water causes depression of the boiling point.

The depression in freezing point (ΔTf) can be calculated using the relation:

ΔTf = i.Kf.m,

where, ΔTf is the depression in freezing point.

i is the van 't Hoff factor.

van 't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass. For most non-electrolytes dissolved in water, the van 't Hoff factor is essentially 1.

Kf is the molal depression constant of water.

m is the molality of the solution (m = 1.0 m, for all solutions).

(1) NaCl:

i for NaCl = no. of particles produced when the substance is dissolved/no. of original particle = 2/1 = 2.

∴ ΔTb for (NaCl) = i.Kb.m = (2)(Kf)(1.0 m) = 2(Kf).

(2) MgCl₂:

i for MgCl₂ = no. of particles produced when the substance is dissolved/no. of original particle = 3/1 = 3.

∴ ΔTb for (MgCl₂) = i.Kb.m = (3)(Kf)(1.0 m) = 3(Kf).

(3) NaCl:

i for KBr = no. of particles produced when the substance is dissolved/no. of original particle = 2/1 = 2.

∴ ΔTb for (KBr) = i.Kb.m = (2)(Kf)(1.0 m) = 2(Kf).

(4) AlCl₃:

i for AlCl₃ = no. of particles produced when the substance is dissolved/no. of original particle = 4/1 = 4.

∴ ΔTb for (CoCl₃) = i.Kb.m = (4)(Kf)(1.0 m) = 4(Kf).

So, the ionic compound will lower the freezing point the most is: AlCl₃

4 0

3 years ago

Read 2 more answers

Which group will have a charge of +2 when ionized?

inysia [295]

Answer:

Alkaline earth metals

Explanation:

Group 2 has 2 valence electrons that they lose when being ionized, thus making their charge 2+.

5 0

3 years ago

Read 2 more answers

Plzzzzz help me to solve this question.

aleksklad [387]

Answer:

Explanation:

A1. Chemical indicator, any substance that gives a visible sign, usually by a colour change, of the presence or absence of a threshold concentration of a chemical species, such as an acid or an alkali in a solution. An example is the substance called methyl yellow, which imparts a yellow colour to an alkaline solution.

A2. The reaction of an acid with a base is called a neutralization reaction. The products of this reaction are a salt and water. ... For example, the reaction of hydrochloric acid, HCl, with sodium hydroxide, NaOH, solutions produces a solution of sodium chloride, NaCl, and some additional water molecules

A3. Methyl orange has the property to color alkaline and neutral water yellow. If the water becomes acidic, it turns red immediately.

3 0

3 years ago