Answer:

1,8066 x 1024 atoms

Explanation:

1 mole of chromium contains 6,022 x 1023 atoms

so

3 moles of chromium contains 3 times as many atoms

3 x 6,022 x 1023 = 1,8 066 x 1024

5 0

3 years ago

In Europe, gasoline efficiency is measured in km/L. If your car's gas mileage is 36.0mi/gal , how many liters of gasoline would

Zigmanuir [339]

$36 \frac{mi}{gal} * \frac{1 km}{0.6214 mi}* \frac{1 gal}{3.78 L} = 15.3 \frac{km}{L}

142/15.3=9.27L$

3 0

3 years ago

Which value is most likely to be the pH of a salt that is formed by the reaction of a strong acid and a weak base?

Mice21 [21]

In a hydrolysis reaction between a strong acid and a weak base, the salt formed will have a pH less than 7. By virtue of this phenomenon between weak bases and strong acids, the anion of the strong acid will fail to attract the hydrogen ion, while the cation from the weak base will donate a proton to the water forming a hydronium ion.

7 0

3 years ago

A skateboarder rolls off a 2.5 m high bridge into the river. If the skateboarder was originally moving at 7.0 m/s, how much time

saul85 [17]

Answer:

t = 0.714 s and x = 5.0 m

Explanation:

This is a projectile throwing exercise, in this case when the skater leaves the bridge he goes with horizontal speed

vₓ = 7.0 m / s

Let's find the time it takes to get to the river

y = y₀ + v_{oy} t - ½ g t²

the initial vertical speed is zero and when it reaches the river its height is zero

0 = y₀ + 0 - ½ g t²

t = $\sqrt{\frac{2y_o}{g} }$

t = ra 2 2.5 / 9.8

t = 0.714 s

the distance traveled is

x = vₓ t

x = 7.0 0.714

x = 5.0 m

3 0

3 years ago