What other scientific fields are included in earth science?

Which of the following statements best describes why a solution of 6.00 g of Ca(NO3)2?in 30.0 g of water has a greater boiling-p

sukhopar [10]

Boiling-point elevation is a colligative property.

That means, the the boiling-point elevation depends on the molar content (fraction) of solute.

The dependency is ΔTb = Kb*m

Where ΔTb is the elevation in the boiling point, kb is the boiling constant, and m is the molality.

A solution of 6.00 g of Ca(NO3) in 30.0 g of water has 4 times the molal concentration of a solution of 3.00 g of Ca(NO3)2 in 60.0 g of water.:

(6.00g/molar mass) / 0.030kg = 200 /molar mass
(3.00g/molar mass) / 0.060kg = 50/molar mass

=> 200 / 50 = 4.

Then, given the direct proportion of the elevation of the boiling point with the molal concentration, the solution of 6.00 g of CaNO3 in 30 g of water will exhibit a greater boiling point elevation.

Or, what is the same, the solution with higher molality will have the higher boiling point.

5 0

3 years ago

Which of the following possess the greatest concentration of hydroxide ions?

jek_recluse [69]

Answer : The correct option is (d) a solution of 0.10 M NaOH

Explanation :

(a) a solution of pH 3.0

First we have to calculate the pOH.

$pH+pOH=14\\\\pOH=14-pH\\\\pOH=14-3.0=11$

Now we have to calculate the $OH^-$ concentration.

$pOH=-\log [OH^-]$

$11=-\log [OH^-]$

$[OH^-]=1.0\times 10^{-11}M$

Thus, the $OH^-$ concentration is, $1.0\times 10^{-11}M$

(b) a solution of 0.10 M $NH_3$

As we know that 1 mole of $NH_3$ is a weak base. So, in a solution it will not dissociates completely.

So, the $OH^-$ concentration will be less than 0.10 M

(c) a solution with a pOH of 12.

We have to calculate the $OH^-$ concentration.

$pOH=-\log [OH^-]$

$12=-\log [OH^-]$

$[OH^-]=1.0\times 10^{-12}M$

Thus, the $OH^-$ concentration is, $1.0\times 10^{-12}M$

(d) a solution of 0.10 M NaOH

As we know that $NaOH$ is a strong base. So, it dissociates to give $Na^+$ ion and $OH^-$ ion.

So, 0.10 M of $NaOH$ in a solution dissociates to give 0.10 M of $Na^+$ ion and 0.10 M of $OH^-$ ion.

Thus, the $OH^-$ concentration is, 0.10 M

(e) a $1\times 10^{-4}M$ solution of $HNO_2$

As we know that 1 mole of $HNO_2$ in a solution dissociates to give 1 mole of $H^+$ ion and 1 mole of $NO_2^-$ ion.

So, $1\times 10^{-4}M$ of $HNO_2$ in a solution dissociates to give $1\times 10^{-4}M$ of $H^+$ ion and $1\times 10^{-4}M$ of $NO_2^-$ ion.

The concentration of $H^+$ ion is $1\times 10^{-4}M$

First we have to calculate the pH.

$pH=-\log [H^+]$

$pH=-\log (1.0\times 10^{-4})$

$pH=4$

Now we have to calculate the pOH.

$pH+pOH=14\\\\pOH=14-pH\\\\pOH=14-4=10$

Now we have to calculate the $OH^-$ concentration.

$pOH=-\log [OH^-]$

$10=-\log [OH^-]$

$[OH^-]=1.0\times 10^{-10}M$

Thus, the $OH^-$ concentration is, $1.0\times 10^{-10}M$

From this we conclude that, a solution of 0.10 M NaOH possess the greatest concentration of hydroxide ions.

Hence, the correct option is (d)

3 0

3 years ago

What is the purpose of the catalyst?

Hitman42 [59]

Its C

a catalyst speeds up a reaction by offering the reaction an alternative reaction pathway with a lower activation energy

hope that helps

5 0

3 years ago

Which discipline of Earth and space science is concerned with the study of the planets and stars?

sweet-ann [11.9K]

Answer:

The discipline of Earth and space science is concerned with the study of the planets and stars is

A. Astronomy

Explanation:

A.Astronomy:

'Astron' means stars and 'nomos' means laws. So astronomy is the study of stars , planets and space

B. biology

It is derived from Greek word : 'Bios' means life and 'logos' means study.

Biology is study of life, living organism ,structure of organisms,evolution

C.Geology

It is the earth science which includes the study of rocks and solid earth, what it is made of and how it has changed .

D. Oceanography

It is the study of physical and biological aspects of oceans

7 0

3 years ago

How to keep pipes from freezing during power outage?.

Maurinko [17]

Answer: Running water, even at a trickle, helps prevent pipes from freezing. If you decide to use fuel-burning equipment, such as a kerosene heater, ensure it is vented to outside and kept clear of any vents. Keep garage doors closed if there are water supply lines in the garage.

Explanation:

8 0

2 years ago

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