Answer:
A: 20 km/h, B: 10 km/h
Explanation:
Speed of Vehicle A = 40-20/ 2-1
=20 km/h
If A is 20km/h, B is 10km/h as given in option
Answer:
70.0 %
Explanation:
Step 1: Given data
- Mass of nitrogen (mN): 74.66 g
- Mass of the compound (mNxOy): 250 g
Step 2: Calculate the mass of oxygen (mO) in the compound
The mass of the compound is equal to the sum of the masses of the elements that form it.
mNxOy = mN + mO
mO = mNxOy - mN
mO = 250 g - 74.66 g = 175 g
Step 3: Determine the percent composition of oxygen in the sample
We will use the following expression.
%O = mO / mNxOy × 100%
%O = 175 g / 250 g × 100% = 70.0 %
Oxygen has 8 electrons it takes 2 electrons to get config of neon and 2 electros mean -2 charge
Friction. Imagine rubbing your hand against a carpet and how it gets hot even though you are pushing it afar. That is friction.
Divide the mass of the compound in grams by the molar mass you just calculated. The answer is the number of moles of that mass of compound.
I hope it helps