They are all examples of chemical formulas
The service rating of passengers car and commercial automotive motor oils
First figure out how many grams must freeze and then convert the grams to moles.
<span>Hf = -334 J/g. Convert this to KJ/g by dividing by 1000. (There are 1000 Joules in a kJ). </span>
<span>Hf = -334 J/g ÷ 1000 J/kj = -0.334 kJ/g </span>
<span>Now, divide 100 kJ by -0.334 kJ/g (see how the units are lining up?) </span>
<span>100 kJ ÷ -0.334 kJ/g = 299 g </span>
<span>Now convert this to moles by dividing by the molecular weight of water (18.0g/mole). </span>
<span>299 ÷ 18.0 = 16.6 moles </span>
Answer:
The volume is 13, 69 L
Explanation:
We use the formula PV=nRT. We convert the temperature in Celsius into Kelvin and the pressure in mmHg into atm.
0°C= 273K---> 56°C= 56 + 273= 329K
760 mmHg----1 atm
719 mmHg----x= (719 mmHgx 1 atm)/760 mmHg= 0,95 atm
PV=nRT ---> V= (nRT)/P
V=( 0,482 molx 0,082 l atm/K mol x 329K)/0,95 atm
<em>V=13,68778526 L</em>
H2SO4 + 2RbOH -> Rb2SO4 + 2H2O
If you want an explanation, keep reading.
In the first portion, there are two hydrogen ions and four sulfate ions.
The second portion has one rubidium ions and one hydroxide ion.
On the other side of the equation, in order to keep those two rubidiums balanced, you'll need to add a two at the beginning of the second portion, but in that process you are giving a second hydroxide value.
Back to the right side, there is there is water (H2O).
On the first portion, there were two hydrogen ions. The second portion also has two hydroxides because of the value change (adding the two to the front).
So on the fourth portion, you'd have to add another two so you could balance the four hydrogen ions (H2 and 2OH) and the two oxygen ions (2OH).
I hope this was easy to understand.