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3 years ago

Which statement is true?

Chemistry

1 answer:

dimulka [17.4K]3 years ago

6 0

Answer:

A I think

Explanation:

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A diesel truck produces 47.5kJ of useful output energy from 125kJ of diesel fuel.what is the truck efficiency?.show the solution

Alex Ar [27]

You have to do a report :
$\frac{E_f}{E_i} = \frac{47,5}{125} = 0,38$

So the truck efficiency is 38%.

7 0

3 years ago

When 61.6 g of alanine (C3H7NO2) are dissolved in 1150. g of a certain mystery liquid X, the freezing point of the solution is 2

MrRissso [65]

Answer:

Explanation:

From the given information:

TO start with the molarity of the solution:

$= \dfrac{61.6 \ g \times \dfrac{1 \ mol \ C_3H_7 NO_3}{89.1 \ g} }{1150 \ g \times \dfrac{1 \ kg}{1000 \g }}$

= 0.601 mol/kg

= 0.601 m

At the freezing point, the depression of the solution is $\Delta \ T_f = T_{solvent}- T_{solution}$

$\Delta \ T_f = 2.9 ^0 \ C$

Using the depression in freezing point, the molar depression constant of the solvent $K_f = \dfrac{\Delta T_f}{m}$

$K_f = \dfrac{2.9 ^0 \ C}{0.601 \ m}$

$K_f = 4.82 ^0 C / m}$

The freezing point of the solution $\Delta T_f = T_{solvent} - T_{solution}$

$\Delta T_f = 7.3^ 0 \ C$

The molality of the solution is:

$= \dfrac{61.6 \ g \times \dfrac{1 \ mol \ NH_4Cl}{53.5 \ g} }{1150 \ g \times \dfrac{1 \ kg}{1000 \g }}$

Molar depression constant of solvent X, $K_f = 4.82 ^0 \ C/m$

Hence, using the elevation in boiling point;

the Vant'Hoff factor $i = \dfrac{\Delta T_f}{k_f \times m}$

$i = \dfrac{7.3 \ ^0 \ C}{4.82 ^0 \ C/m \times 1.00 \ m}$

$\mathbf {i = 1.51 }$

3 0

2 years ago

Cuales elementos tienen solo un electrón de valencia

aleksley [76]

Answer:

En el caso del sodio, la valencia es 1, ya que tiene un solo electrón de valencia, si pierde un electrón se queda con el último nivel completo.

Explanation:

Grupo de la tabla periódica Electrones de valencia

Grupo 14 (IV) (Grupo del carbono) 4

Grupo 15 (V) (Grupo del nitrógeno ) 5

6 0

3 years ago

Which is a base unit used in the metric system?

DaniilM [7]

Answer:

<h2> Quarts </h2><h2>Litres </h2><h2>Pints </h2><h2>Degrees Fahrenheit. </h2>

ASK for more

4 0

3 years ago

Which of the following is an example of a negative tropism?

salantis [7]

C—stems and leaves growing upward?

7 0

2 years ago