CHEM 120 EXAM 1 FULLY SOLVED EXAM PAPER
GRADED A+
◉ How to convert Celsius to Fahrenheit.
Answer: F= 9/5 *c + 32
◉ How to convert Fahrenheit to Celsius.
Answer: C= 5/9(*F-32)
◉ How to convert Celsius to Kelvin.
Answer: K= *c + 273.15
◉ What are measured numbers?.
Answer: Numbers you obtain after measuring a quantity (ex. Height,
Weight, Temperature, etc.)
◉ What are Significant Figures?.
Answer: The number of digits that express your answer/result to
the true measured precision
◉ Sig Fig Rules.
Answer: 1. All nonzero digits are significant (ex. 1363 has 4 sig figs)
, 2. Zeroes between two sig figs are themselves significant (ex. 10003
has 5 sig figs, 100.03 has 5 sig figs, 0.10003 has 5 sig figs)
3. Zeroes at the beginning of a number are NEVER significant (ex.
0.00897 has 3 sig figs b/c the sf at the beginning are not significant
*placeholders*)
4. Zeroes at the end of a number are significant if a decimal point is
written in the number (ex. 2..300 has 4 sf, 230.0 has 4 sf, 2300. has 4
sf. However, 2300 doesn't have a decimal therefor it is not
significant. Has 2, 3, or 4 sf)
◉ When are answers rounded to the least significant DECIMAL
place?.
Answer: When you are adding or subtracting (ex. 2.63 + 1.2 = 3.83
but rounds to 3.8 because the smallest amount of decimal places is 1
b/c of the 1.2)
◉ When are answers rounded to the number of digits that
corresponds to the least number of sig figs in ANY of the numbers
used in a calculation?.
Answer: When you are multiplying or dividing (ex. 2.61 x 1.008 x
6.0000 = 15.7248 which rounds to 15.7 due to the fact the smallest
sf number is 3 b/c of 2.61)
◉ What are exact numbers?.
GRADED A+
◉ How to convert Celsius to Fahrenheit.
Answer: F= 9/5 *c + 32
◉ How to convert Fahrenheit to Celsius.
Answer: C= 5/9(*F-32)
◉ How to convert Celsius to Kelvin.
Answer: K= *c + 273.15
◉ What are measured numbers?.
Answer: Numbers you obtain after measuring a quantity (ex. Height,
Weight, Temperature, etc.)
◉ What are Significant Figures?.
Answer: The number of digits that express your answer/result to
the true measured precision
◉ Sig Fig Rules.
Answer: 1. All nonzero digits are significant (ex. 1363 has 4 sig figs)
, 2. Zeroes between two sig figs are themselves significant (ex. 10003
has 5 sig figs, 100.03 has 5 sig figs, 0.10003 has 5 sig figs)
3. Zeroes at the beginning of a number are NEVER significant (ex.
0.00897 has 3 sig figs b/c the sf at the beginning are not significant
*placeholders*)
4. Zeroes at the end of a number are significant if a decimal point is
written in the number (ex. 2..300 has 4 sf, 230.0 has 4 sf, 2300. has 4
sf. However, 2300 doesn't have a decimal therefor it is not
significant. Has 2, 3, or 4 sf)
◉ When are answers rounded to the least significant DECIMAL
place?.
Answer: When you are adding or subtracting (ex. 2.63 + 1.2 = 3.83
but rounds to 3.8 because the smallest amount of decimal places is 1
b/c of the 1.2)
◉ When are answers rounded to the number of digits that
corresponds to the least number of sig figs in ANY of the numbers
used in a calculation?.
Answer: When you are multiplying or dividing (ex. 2.61 x 1.008 x
6.0000 = 15.7248 which rounds to 15.7 due to the fact the smallest
sf number is 3 b/c of 2.61)
◉ What are exact numbers?.
