All categories

2 years ago

How long will it take a coach travelling at 90 km/h to travel 300 km along a highway?

Chemistry

1 answer:

love history [14]2 years ago

4 0

Answer:

3.3 hours

Explanation:

Given data:

Speed of coach = 90 km/h

Distance to be covered = 300 km

Time taken = ?

Solution:

Formula:

v = d/ t

v = speed

d = distance

t = time

Now we will put the values in formula,

v = d/ t

t = d/ v

t = 300 km / 90 km/h

t = 3. 3 h

You might be interested in

For no2−, write an equation that shows how the anion acts as a base. express your answer as a chemical equation. identify all of

katrin [286]

Hello!

Bases are defined by Arrhenius as substances which release OH⁻ ions when dissolved in water. NO₂⁻ complies with this definition by the chemical reaction that is shown below:

NO₂⁻(aq) + H₂O (l) HNO₂ (aq) + OH⁻(aq)

Have a nice day!

5 0

2 years ago

Read 2 more answers

Exactly 1.0 mol N2O4 is placed in an empty 1.0-L container and allowed to reach equilibrium described by the equation N2O4(g) 2N

Amanda [17]

Answer : The correct option is, (a) 0.44

Explanation :

First we have to calculate the concentration of $N_2O_4$ .

$\text{Concentration of }N_2O_4=\frac{\text{Moles of }N_2O_4}{\text{Volume of solution}}$

$\text{Concentration of }N_2O_4=\frac{1.0moles}{1.0L}=1.0M$

Now we have to calculate the dissociated concentration of $N_2O_4$ .

The balanced equilibrium reaction is,

$N_2O_4(g)\rightleftharpoons 2NO_2(aq)$

Initial conc. 1.0 M 0

At eqm. conc. (1.0-x) M (2x) M

As we are given,

The percent of dissociation of $N_2O_4$ = $\alpha$ = 28.0 %

So, the dissociate concentration of $N_2O_4$ = $C\alpha=1.0M\times \frac{28.0}{100}=0.28M$

The value of x = $C\alpha$ = 0.28 M

Now we have to calculate the concentration of $N_2O_4\text{ and }NO_2$ at equilibrium.

Concentration of $N_2O_4$ = 1.0 - x = 1.0 - 0.28 = 0.72 M

Concentration of $NO_2$ = 2x = 2 × 0.28 = 0.56 M

Now we have to calculate the equilibrium constant for the reaction.

The expression of equilibrium constant for the reaction will be:

$K_c=\frac{[NO_2]^2}{[N_2O_4]}$

Now put all the values in this expression, we get :

$K_c=\frac{(0.56)^2}{0.72}=0.44$

Therefore, the equilibrium constant $K_c$ for the reaction is, 0.44

8 0

2 years ago

What volume (ml) of a 0.2450 m koh(aq) solution is required to completely neutralize 55.25 ml of a 0.5440 m h3po4(aq) solution?

Nonamiya [84]

<span>Answer: It depends on what came after "0.5440 M H...". If it was a monoprotic acid, like HCl, the calculation would go like this: (55.25 mL) x (0.5440 M acid) x (1 mol KOH / 1 mol acid) / (0.2450 M KOH) = 122.7 mL KOH If it was a diprotic acid, like H2SO4, like this: (55.25 mL) x (0.5440 M acid) x (2 mol KOH / 1 mol acid) / (0.2450 M KOH) = 245.4 mL KOH If it was a triprotic acid, like H3PO4, like this: (55.25 mL) x (0.5440 M acid) x (3 mol KOH / 1 mol acid) / (0.2450 M KOH) = 368.0 mL KOH</span>

5 0

2 years ago

Wine has a pH of 3, which means it is __________ times more acidic than tomatoes, which have a pH of 4.

Natasha2012 [34]

Answer:

Explanation:

pH is defined as the negative logarithm of the concentration of hydrogen ions.

Thus,

pH = - log [H⁺]

Thus, from the formula, more the concentration of the hydrogen ions or more the acidic the solution is, the less is the pH value of the solution.

Thus, solution with pH = 3 will be more acidic than solution with pH =4

Thus, concentration of the [H⁺] when pH =3

3 = - log [H⁺]

[H⁺] = 10⁻³ M

For pH = 4, [H⁺] = 10⁻⁴ M

<u>hence, pH = 3 is 10 times more acidic than pH = 4</u>

5 0

2 years ago

The molecular weight of table salt, NaCl, is 58.5 g/mol. A tablespoon of salt weighs 6.37 grams. Calculate the number of moles o

dezoksy [38]

A: 6.37gNaCl

B: 1 mol NaCl

C: 58.5 g NaCl

These answers are correct on e2020 I just got them right.

6 0

2 years ago

Read 2 more answers