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stiv31 [10]
3 years ago
5

How many oxygen atoms are there in 6.00 g of sodium dichromate, na2cr2o7?

Chemistry
1 answer:
mel-nik [20]3 years ago
6 0
Answer is: there are 9,7·10²² atoms of oxygen.
m(Na₂Cr₂O₇) = 6,00 g.
n(Na₂Cr₂O₇) = m(Na₂Cr₂O₇) ÷ M(Na₂Cr₂O₇).
n(Na₂Cr₂O₇) = 6 g ÷ 262 g/mol.
n(Na₂Cr₂O₇) = 0,023 mol.
n(Na₂Cr₂O₇) : n(O) = 1 : 7.
n(O) = 7 · 0,023 mol.
n(O) = 0,161 mol.
N(O) = 0,161 mol · 6,022·10²³ 1/mol.
N(O) = 9,7·10²².
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C₁₅H₁₁COONa --> C₁₅H₁₁COO⁻ + Na⁺

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3 years ago
Calculate the mass of water produced when 2.06 g of butane reacts with excess oxygen.
dem82 [27]
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8 0
3 years ago
Which of the following is the best piece of laboratory glassware for preparing 500.0 mL of an aqueous solution of a solid?
Leni [432]

Answer:

The correct answer is option A.

Explanation:

Volumetric flask  : A glass ware with round lower body with flat bottom and with thin cylindrical neck along with mark which indicates the specific volume filled to that mark.It is used in preparation of standard solution of compound with desired concentration with fixed volume.

Erlenmeyer flask : is a flask with conical shape with flat bottom used in titration  experiments to carry out reaction with fixed volume of solution.

Test tube : Small cylindrical tube with rounded bottom used to observe reaction in between reactant taken in small amount.

Graduated beaker : Laboratory glassware used measure larger volumes of solution or to mix or stir solutions and liquids.

Graduated cylinder : Laboratory thin cylindrical glassware with accurate marking of volume used to measure an accurate volume of solutions or liquids required in an experiment.

<em><u>Volumetric flask</u></em> is the best piece of laboratory glassware for preparing 500.0 mL of an aqueous solution of a solid

8 0
3 years ago
Read 2 more answers
3. A student measured 15.0 grams of ice in a beaker. The beaker was then
gregori [183]

Answer:

The heat that was used to melt the 15.0 grams of ice at 0°C is 4,950 Joules

Explanation:

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The initial temperature of the ice = 0°C

The final temperature of the ice = 0°C

The latent heat of fusion of ice = 330 J/g

The heat required to melt a given mass of ice = The mass of the ice to be melted × The latent heat of fusion of ice

Therefore, the heat, Q, required to melt 15.0 g of ice = 15.0 g × 330 J/g = 4,950 J

The heat that was used to melt the 15.0 grams of ice = 4,950 Joules.

3 0
3 years ago
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Andre45 [30]

Answer:

d) Combustión.

Explanation:

¡Hola!

En este caso, dado que estamos enfocados en el concepto de cambio químico, el cual se caracteriza por exhibir un cambio en la composición e identidad de las sustancias iniciales (reactivos) a otras finales (productos).

Ahora bien, como se nos dice que los productos de este cambio químico son energía, agua y dióxido de carbono, inferimos que el nombre de este proceso es d) Combustión, por ejemplo la combustion del gas natural para calentar nuestras comidas en la cocina.

¡Saludos!

6 0
3 years ago
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