<u>Answer:</u> The correct answer is Option D.
<u>Explanation:</u>
We are given that car travels with a speed of 80 km/hr and we need to convert it into hm/s.
For that we use the conversions:
1 kilometer = 10 hectometer
And, 1 hour = 3600 seconds
To convert the quantity into hm/s, we multiply the numerator which is 80 by 10 to convert the whole quantity into hm/hr and now, to convert the result into hm/s finally, we divide the result by 3600.
Hence, the correct answer is option D.
Answer:
"1 M" will be the right solution.
Explanation:
The given values are:
Number of moles,
= 2 moles
Volume of solution,
= 2000 mL
or,
= 2 L
Now,
The molarity of the solution will be:
=
On substituting the values, we get
=
=
Answer:
544.522 Hours
Explanation:
a) Mass = 12.5 kg = 12500 g
Now, Number of moles is given as
No of moles = Mass of Cr / Molar mass of Cr
= 240.38 moles
3 mols of electrons are required
Converting moles of e- to coulombs of charge, (1 mol of electrons = 96500 C )
Q =721.14 mol×96500 C/mol
=69590010 of charge
We know that, Q = I×t
where Q is charge, I is current and t is time required.
=196281.97 seconds
=544.522 Hours