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2 years ago

What is an atomic weight?

1 answer:

3 0

The average weight of an atom of an element, formerly based on the weight of one hydrogen atom taken as a unit or on 1/16 (0.0625) the weight of an oxygen atom, but after 1961 based on 1/12 the weight of the carbon-12 atom.

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HOW DO SCIENTISTS FORECAST SPACE WEATHER AND WHY

Fittoniya [83]

<span>Much like tornado watchers look to the skies for clues that a twister is forming, NASA and university scientists are watching the Sun in an effort to better predict space weather – blasts of particles from the Sun that impact the magnetosphere, the magnetic bubble around the Earth.</span>

8 0

3 years ago

Match the following aqueous solutions with the appropriate letter.

Alla [95]

Answer:

Explanation:

When a salt is dissolved , it increases the boiling point . Increase in boiling point depends upon number of ions . So it is a colligative property .

.19 m AgNO₃ . Each molecule will ionize into two ions . So effective molar concentration is 0.19 x 2 = .38 m

0.17 m CrSO4.Each molecule will ionize into two ions . So effective molar concentration is 0.17 x 2 = .34 m

0.13 m Mn(NO₃)₂. Each molecule will ionize into three ions . So effective molar concentration is 0.13 x 3 = .39 m

0.31 m Sucrose(nonelectrolyte). Molecules will not ionize . So effective molar concentration is 0.31 x 1 = .31 m

Higher the molar concentration , greater the depression in boiling point .

So lowest boiling point is 0.13 m Mn(NO₃)₂.

second highest boiling point is 0.19 m AgNO3.

Third lowest boiling point is 0.17 m CrSO4

Highest boiling point or lowest depression 0.31 m Sucrose.

a . 4

b . 1

c . 2

d . 3

6 0

2 years ago

Equal volumes of H2 and o2 are placed in a balloon and then ignited. Assuming that the reaction goes to completion, which gas wi

Anastasy [175]

You will have excess O2. The ideal gas law dictates that all other variables kept the same, equal volume means equal number of moles.

7 0

2 years ago

Read 2 more answers

The hall reaction of an oxidation-reduction reaction shows that iron gains electrons. What does this electron gain mean for iron

AnnZ [28]

Answer: Iron gains electrons mean It is reduced

Explanation:

Oxidation-reduction reaction or redox reaction is defined as the reaction in which oxidation and reduction reactions occur simultaneously.

Oxidation reaction is defined as the reaction in which a substance looses its electrons. The oxidation state of the substance increases.

$Zn\rightarrow Zn^{2+}+2e^-$

Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced.

$Fe^{2+}+2e^-\rightarrow Fe$

Thus iron gains electrons mean It is reduced

6 0

2 years ago

When carbon is burned in air, it reacts with oxygen to form carbon dioxide. When 15.6 g of carbon were burned in the presence of

NeX [460]

Answer: 5.72 g mass of carbon dioxide was produced

Explanation:

$C+O_2\rightarrow CO_2$

Moles of C = $\frac{\text{mass of carbon}}{\text{molar mass of carbon}}=\frac{15.6 g}{12 g/mol}=1.3 moles$

Mass of $O_2$ reacted = 59.1 g - 17.5 g = 41.6 g

Moles of $O_2\text{ reacted}=\frac{\text{mass of}O_2}{\text{molar mass of}O_2}=\frac{41.6 g}{32 g/mol}=1.3 moles$

According to reaction 1 mole $O_2$ produces 1 mole of $CO_2$ then 1.3 mole of $O_2$ will produce $\frac{1}{1}\times 1.3$ moles of $CO_2$

Mass of $CO_2$ :

=Moles of $CO_2$ × molar mass of $CO_2$ = 1.3 ×44 g/mol =

=57.2 grams

5.72 g mass of carbon dioxide was produced

7 0

2 years ago