Acar travels at a speed of 80 km/h. which of the following is correct to convert the speed of the car to hm/s? [1 km = 10 hm, 1 h = 3600 s] a divide 80 by 3600 b multiply 80 by 3600 c divide 80 by 10 and multiply the result obtained by 3600 d multiply 80 by 10 and divide the result obtained by 3600

The correct answer is Option D.

Explanation:

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.

We need 0.50 L of O2 to react

Explanation:

Step 1: Data given

Volume of carbon monoxide (CO) = 1.0 L (STP)

Step 2: The balanced equation

2CO(g) + O2(g) → 2CO2(g)

Step 3: Calculate moles CO

22.4 L = 1.0 mol

1.0 L = 1.0 / 22.4 L = 0.0446 moles

Step 4: Calculate moles O2

For 2 moles CO we need 1 mol O2 to produce 2 moles CO2

For 0.0446 moles CO we need 0.0446/2 = 0.0223 moles O2

Step 5: Calculate volume O2

1.0 mol = 22.4 L

0.0223 moles = 0.50 L

We need 0.50 L of O2 to react