Unit 1
Scientific Measurements
Scientific Measurements
What kind of glassware do you use to precisely measure a solvent?
A graduated cylinder.
Convert –55ºC to the Kelvin scale?
218 ºK
Kelvin = Celsius + 273
An atom of Iodine has 53 protons and 55 neutrons. What is its mass number?
Iodine - 108
An ionic compound is made of a metal and a ______
non-metal
Na metal
Cl non-metal
NaCl
What is the oxidation number of an element that is alone?
Always 0
Name a piece of quantitative data and qualitative data?
A.) quantitative =
B.) qualitative =
A.) Quantitative observation is when numbers are included in the observed data, such as:Boiling point is 150 degrees C
B.) Qualitative observation is any data that is a non-numerical quality. Such as: The flower has a long green stem.
Give an example of an element?
Give an example of a compound?
An element is on the periodic table.
Na , H₂ , O₂ ,
A compound is 2 or more elements together.
NaCl , H₂O , C₁₂H₂₂O₁₁
What did Rutherford discover about the structure of the atom?
An atom contains a small, dense, positively charged central region.
Name any covalent compound
what are the electrons doing in a covalent molecule?
C₁₂H₂₂O₁₁ (or any non-metal and non-metal)
Molecules / Covalent compounds share electrons
Which term describes the change that occurs in the element Chromium, Cr when it bonds to oxygen and becomes the ion Cr+3?
The Chromium was Oxidized.
(or Oxidation )
The Sun's diameter is 1,392,000 km. What is this number in scientific notation?
1.392000 * 10^6 km
A.) Name an intensive property:
B.) Name an extensive property:
A.) Intensive properties: do not change with size.
- density, color, smell, shape, boiling point.
B.) Extensive properties: change with size.
- mass, volume, width, length, intensity of smell
Who decided to rearrange the periodic table by atomic number? (This is what we use today.)
Moseley.
What is the formula for zinc chloride ?
Zn2+ Cl1-
Answer: ZnCl2
When an element gains electrons is it
oxidized or reduced or both?
When an element gains electrons it is Reduced.
OIL RIG
Oxidation is Loss - OIL
Reduction is Gained - RIG
Accuracy - Is hitting the goal target.
Precision - Is when your values are close together.
If you keep a liquid sample at the same temperature but increase the pressure drastically, the liquid will turn into a...(solid, liquid, gas or plasma)
Solid
The Cathode ray experiment was done by an English physicists named J. J. Thomson. Using Cathode ray tubes which particle was discovered?
electron
What is the chemical formula for hydrosulfuric acid?
H₂S
Here is why:
H ¹⁺ S²⁻
__ Fe(s) + __ H2SO4(aq) → __ Fe2(SO4)3(aq) + __ H2(g)
What type of reaction is this?
Single Replacement
Mr Steal Yo Girl
When 723,455 g is divided by 90.020 mL, what will the correct number of significant figures in the result be?
5 significant figures
Argon, krypton, and xenon are in what family?
(The name not the number)
Noble Gases
( He , Ne , Ar , Kr , Xe , Rn )
What is the average atomic mass of Titanium, if a sample of Titanium is:
25.60% Titanium-22 and 74.40% Titanium-24?
23.488 amu
NaOH(aq) + HCl(aq) --> NaCl(aq) + H₂O(l)
35.00 g 45.00 g ? 18.00 g
In the above acid base reaction, how much salt was produced?
35.00 + 45.00 = ? +18.00
80.00 = ? + 18.00
80.00 - 19.00 = ? = 62.00 grams
What are the balanced coefficients for the following combustion reaction:
__C3H8(l) + __O2(g) --> __CO2(g) + __H2O(l)
Answer: 1, 5, 3, 4
1 C3H8(l) + 5 O2(g) --> 3 CO2(g) + 4 H2O(l)