<span>To find the enthalpy change per mole of a substance A in a reaction between two substances A and B, the substances are added to a calorimeter and the initial and final temperatures (before the reaction started and after it has finished) are noted</span>
Look at a periodic table. Ptable.com is great. Amu= g/mol which is found under the symbol. divide the number heavier by the total and multiply by 100 to get percent.
Answer:
leading zeroes to the left of a decimal point. and trailing zeros to the left of an invisible decimal point.
Explanation:
- All nonzero digits are significant figures. Example: 713 has three significant figures. 18,991 has five significant figures.
- Zeros located between two nonzero digits are significant figures. Example: 505 has three significant figures. 17,009 has five significant figures.
- Zeros at the ends of numbers are only significant if there is a decimal point in the number. Example: 502.00 has five significant figures (5,0,2,0,0). 5020 has three significant figures (5,0,2) 100,000 has one significant figure (1)
- Zeros that come before the first nonzero digit are not significant. Example: 0.0007 has one significant figure (7). 0.0970 has three significant figures (9,7,0)
Answer:
The answer to your question is Volume = 11.4 L
Explanation:
Data
Volume 1 = V1 = 6 L
Pressure 1 = P1 = 1 atm
Temperature 1 = T1 = 22°C
Volume 2 = V2 = ?
Pressure 2 = 0.45 atm
Temperature 2 = -21°C
Process
1.- Convert temperature (°C) to °K
T1 = 273 + 22 = 295°K
T2 = 273 + (-21) = 252°K
2.- Use the combined gas law to solve this problem
P1V1 / T1 = P2V2 / T2
-Solve for V2
V2 = P1V1T2 / T1P2
-Substitution
V2 = (6)(1)(252) / (295)(0.45)
- Simplification
V2 = 1512 / 132.75
- Result
V2 = 11.38 L
