CHEM-111G-GENERAL CHEMISTRY Exam Prep with
Questions & CORRECT Verified ANSWERS |
rules for recording significant figures - ✔✔Non-zero digits are always significant.
All zeros between other significant digits are significant.
The number of significant figures is determined by starting with the leftmost non-zero digit. The
leftmost non-zero digit is sometimes called the most significant digit or the most significant
figure. For example, in the number 0.004205, the '4' is the most significant figure. The left-hand
'0's are not significant. The zero between the '2' and the '5' is significant.
rules for rounding significant figures - ✔✔1. If the digit to the right of the last sf is less than
5, do not change the last sf (2.532->2.53)
2. If the digit to the right of the last sf is greater than 5, round up the last sf (2.536->2.54)
(3+4-rule of 5-even)
3. If the digit to the right of the last sf are a 5 followed by a nonzero digit, round up the last sf
(2.531->2.54)
4. If the digits to the right of the last sf are a 5 followed by a 0 or no other number, look at the
last sf. If it is odd, round it up; if it is even, do not round up (2.5350->2.54 or 2.5250->2.52)
significant figures and math operation - ✔✔rules for multiple operation and division, the
results should have the same kind of sig figures as the number with the fewest amounts of sig
Rules for addition and subtraction - ✔✔the answer has the same number of decimal places
as the original number with the fewest decimal places
Atomic models in order - ✔✔Dalton's Atomic Theory In \ (1803,\) John Dalton developed a
theory of the structure of matter based on the law of chemical combination. The main
postulates of this theory are: ...
Thomson's Atomic Model J.J Thomson made the first attempt at explaining the fine structure of
the atom. ...
, Rutherford's Model of an Atom ...
According to Rutherford Model of an Atom ..
Bohr atomic model - ✔✔Atoms described as electrons orbiting the nucleus in well defined
paths.
Atomic number (Z number) - ✔✔the number of protons in an atom
mass number - ✔✔the total number of protons and neutrons in the nucleus of an atom
isotopes - ✔✔Atoms of the same element that have different numbers of neutrons
concepts definition matters - ✔✔Matter is made up of atoms
elements - ✔✔A molecule composed of one kind of atom; cannot be broken into simpler
units by chemical reactions.
Compound - ✔✔substance formed by the chemical combination of two or more elements in
definite proportions
pure substance - ✔✔A substance made of only one kind of matter and having definite
properties.
Mixtures - ✔✔A combination of two or more substances that are not chemically combined
heterogenous mixture - ✔✔A mixture with uneven distribution of different substances,
solids, liquids, gases.
Questions & CORRECT Verified ANSWERS |
rules for recording significant figures - ✔✔Non-zero digits are always significant.
All zeros between other significant digits are significant.
The number of significant figures is determined by starting with the leftmost non-zero digit. The
leftmost non-zero digit is sometimes called the most significant digit or the most significant
figure. For example, in the number 0.004205, the '4' is the most significant figure. The left-hand
'0's are not significant. The zero between the '2' and the '5' is significant.
rules for rounding significant figures - ✔✔1. If the digit to the right of the last sf is less than
5, do not change the last sf (2.532->2.53)
2. If the digit to the right of the last sf is greater than 5, round up the last sf (2.536->2.54)
(3+4-rule of 5-even)
3. If the digit to the right of the last sf are a 5 followed by a nonzero digit, round up the last sf
(2.531->2.54)
4. If the digits to the right of the last sf are a 5 followed by a 0 or no other number, look at the
last sf. If it is odd, round it up; if it is even, do not round up (2.5350->2.54 or 2.5250->2.52)
significant figures and math operation - ✔✔rules for multiple operation and division, the
results should have the same kind of sig figures as the number with the fewest amounts of sig
Rules for addition and subtraction - ✔✔the answer has the same number of decimal places
as the original number with the fewest decimal places
Atomic models in order - ✔✔Dalton's Atomic Theory In \ (1803,\) John Dalton developed a
theory of the structure of matter based on the law of chemical combination. The main
postulates of this theory are: ...
Thomson's Atomic Model J.J Thomson made the first attempt at explaining the fine structure of
the atom. ...
, Rutherford's Model of an Atom ...
According to Rutherford Model of an Atom ..
Bohr atomic model - ✔✔Atoms described as electrons orbiting the nucleus in well defined
paths.
Atomic number (Z number) - ✔✔the number of protons in an atom
mass number - ✔✔the total number of protons and neutrons in the nucleus of an atom
isotopes - ✔✔Atoms of the same element that have different numbers of neutrons
concepts definition matters - ✔✔Matter is made up of atoms
elements - ✔✔A molecule composed of one kind of atom; cannot be broken into simpler
units by chemical reactions.
Compound - ✔✔substance formed by the chemical combination of two or more elements in
definite proportions
pure substance - ✔✔A substance made of only one kind of matter and having definite
properties.
Mixtures - ✔✔A combination of two or more substances that are not chemically combined
heterogenous mixture - ✔✔A mixture with uneven distribution of different substances,
solids, liquids, gases.
