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3 years ago

Question 18 of 35

Chemistry

1 answer:

sammy [17]3 years ago

4 0

Answer:

A. Dark-colored moths become common after tree trunks become

dark.

Explanation:

I took the test

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What would barium do to obtain a noble gas structure? gain 2 electrons lose 2 electrons gain 6 electrons lose 6 electrons

Tema [17]

Answer:

Lose two electrons.

Explanation:

Barium is present in group 2.

It is alkaline earth metal.

Its atomic number is 56.

Its electronic configuration is Ba₅₆ = [Xe] 6s².

In order to attain the noble gas electronic configuration it must loses its two valance electrons.

When barium loses it two electron its electronic configuration will equal to the Xenon.

The atomic number of xenon is 54 so barium must loses two electrons to becomes equal to the xenon.

4 0

3 years ago

Plants produce a variety of substances:food,flavoring,drugs,poisons.this is a result of

tatuchka [14]

Answer:

Synthesis

Explanation:

They synthesize these chemicals

7 0

3 years ago

A solution contains an unknown amount of dissolved magnesium. Addition of

Scrat [10]

Taking into account the reaction stoichiometry, 2.13 grams of magnesium was dissolved in the solution.

<h3>Reaction stoichiometry</h3>

In first place, the balanced reaction is:

Mg²⁺(aq) + Na₂CO₃(aq) → MgCO₃(s) + 2 Na⁺(aq)

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:

Mg²⁺: 1 mole
Na₂CO₃: 1 mole
MgCO₃: 1 mole
Na⁺: 2 moles

The molar mass of the compounds is:

Mg²⁺: 24.3 g/mole
Na₂CO₃: 106 g/mole
MgCO₃: 84.3 g/mole
Na⁺: 23 g/mole

Then, by reaction stoichiometry, the following mass quantities of each compound participate in the reaction:

Mg²⁺: 1 mole ×24.3 g/mole= 24.3 grams
Na₂CO₃: 1 mole ×106 g/mole= 106 grams
MgCO₃: 1 mole ×84.3 g/mole=84.3 grams
Na⁺: 2 moles ×23 g/mole= 46 grams

<h3>Mass of magnesium dissolved</h3>

The following rule of three can be applied: If by reaction stoichiometry 1 mole of Na₂CO₃ react with 24.3 grams of magnesium, 0.0877 moles of Na₂CO₃ react with how much mass of magnesium?

$mass of magnesium=\frac{0.0877 moles of Na_{2}C O_{3}x24.3 grams of magnesium }{1 mole of Na_{2}C O_{3}}$

<u><em>mass of magnesium= 2.13 grams</em></u>

Finally, 2.13 grams of magnesium was dissolved in the solution.

Learn more about the reaction stoichiometry:

<u>brainly.com/question/24741074</u>

<u>brainly.com/question/24653699</u>

4 0

2 years ago

I need help ASAP

vova2212 [387]

Answer:

1.4 g/cm3

Explanation:

Density = Mass/Volume

Mass = 21g

Volume = 15cm3

Density = 21/15 = 1.4

8 0

2 years ago

How do you know that oxygen was the gas removed from the volume of air and not another

klio [65]

One way of knowing that oxygen was the gas removed from the volume of air and not another is to know what the volume of air is made of first. When the composition of the volume of air is already identified, then next would be the process of separating these elements from each other and as to which is to be separated first. This would usually lead to knowing their masses, their boiling and freezing points, the temperatures at which they condense, and so on. This is to identify their differences to each other and use those differences to successfully separate those elements to each other.

8 0

3 years ago