Ask question

Ask question

All categories

2 years ago

12

A sprinter set a high school record in track and field, running 200.0 m in 21.3 s. What is the average speed of the sprinter in

kilometers per hour?

1 answer:

Taya2010 [7]2 years ago

3 0

Answer:

33.8km/h

Explanation:

average speed=dostance traveled/time

200/21.3=9.39 m/s

1m/s=3.6km/h

33.8km/h

please give brainliest

You might be interested in

Please give me two properties that glass and plastic always share

mylen [45]

Answer:

both are solids, both are somewhat pliable

6 0

3 years ago

What forces hold molecular solids together?

vodka [1.7K]

Answer:

Molecular solids are held together by relatively weak forces, such as dipole–dipole interactions, hydrogen bonds, and London dispersion forces.

8 0

3 years ago

Read 2 more answers

What is the element name for K2S

aliya0001 [1]

~The picture below shall help :)
-Hope this helped ^_^

5 0

3 years ago

Read 2 more answers

A given atom has 3 protons, 4 neutrons, and 3 electrons. Describe how you can use those three values to describe the structure,

sammy [17]

The atomic number of a neutral atom is equal to the number of protons and the number of electrons of the atom. The atomic weight meanwhile is equal to the sum of the number of protons and number of neutrons. In this case, the atomic number of the atom is 3 and the atomic mass is 7. Hence the element is Lithium, a metal

6 0

4 years ago

Which aqueous solution would have the lowest vapor pressure at 25°c 1 M NaCl?

aleksley [76]

The question is incomplete, here is a complete question.

Which aqueous solution would have the lowest vapor pressure at 25°c.

A) 1 M NaCl

B) 1 M $K_3PO_4$

C) 1 M $C_{12}H_{10}O_{11}$

D) 1 M $MgCl_2$

E) 1 M $C_6H_{12}O_6$

Answer : The correct option is, (B) 1 M $K_3PO_4$

Explanation :

According to the relative lowering of vapor pressure, the vapor pressure of a component at a given temperature is equal to the mole fraction of that component of the solution multiplied by the vapor pressure of that component in the pure state.

1 M means that the 1 moles of solute present in 1 liter of solution.

Formula used :

$\frac{\Delta p}{p^o}=i\times X_B$

where,

$p^o$ = vapor pressure of the pure component (water)

$p_s$ = vapor pressure of the solution

$X_B$ = mole fraction of solute

i = Van't Hoff factor

As we know that the vapor pressure depends on the mole fraction of solute and the Van't Hoff factor.

So, the greater the number of particles of solute dissolved the lower the resultant vapor pressure.

(a) The dissociation of 1.0 M $NaCl$ will be,

$NaCl\rightarrow Na^++Cl^-$

So, Van't Hoff factor = Number of solute particles = $Na^++Cl^-$ = 1 + 1 = 2

(b) The dissociation of 1 M $K_3PO_4$ will be,

$K_3PO_4\rightarrow 3K^{+}+PO_4^{3-}$

So, Van't Hoff factor = Number of solute particles = $3K^{+}+PO_4^{3-}$ = 3 + 1 = 4

(c) The dissociation of 1 M $C_{12}H_{10}O_{11}$ is not possible because it is a non-electrolyte solute. So, the Van't Hoff factor will be, 1.

(d) The dissociation of 1.0 M $MgCl_2$ will be,

$MgCl_2\rightarrow Mg^{2+}+2Cl^{-}$

So, Van't Hoff factor = Number of solute particles = $Mg^{2+}+2Cl^{-}$ = 1 + 2 = 3

(e) The dissociation of 1 M $C_6H_{12}O_{6}$ is not possible because it is a non-electrolyte solute. So, the Van't Hoff factor will be, 1.

From this we conclude that, 1 M $K_3PO_4$ has the highest Van't Hoff factor which means that the solution will exhibit the lowest vapor pressure.

Hence, the correct option is, (B) 1 M $K_3PO_4$

8 0

3 years ago