Intro to Chemistry
Which of the following is not a homogenous mixture?
a) Air
b) sugar dissolved in water
c) Metal Alloys
D) Granite
D) Granite
Which of the following has the most significant figures?
a) 0.007850
b) 150000
c) 1.8200
d) 18.6
c) 1.8200
atoms of the same element with different masses
- aka different number of neutrons
An unknown neutral element X has 17 electrons, what is the element?
Chlorine
Which of the following would you expect to form an anion?
a) potassium
b) Calcium
c) Sulfur
d) Strontium
c) Sulfur
Which of the following would be a chemical change?
1. adding food coloring to water
2. Ice Melting
3. Wood Rotting
4. Stretching a rubber band
3. Wood Rotting
You calculate the temperature of a certain homogenous mixture to be 78.0 F but all of the answers are given in K. What would the answer be?
a) 365 K
b) 348 K
c) 25.6 K
d) 299 K
d) 299 K
What is the charge of a proton, neutron, and electron
Positive, Neutral, Negative
Which of the following elements would be the best at conducting heat and electricity?
a) H
b) Si
c) I
d) Mg
d) Mg
Which of the following is an ionic compound?
a) Mg(OH)2
b) H2O
c) NH3
d) CO2
a) Mg(OH)2
What is the difference between accuracy and precision
Accuracy is how close you are to the true value while precision is how close your values are to each other
(26.5 x 10-4 - 6.02 x 10-5) / (0.02 + 1.82)
a) 1.30 x 10-3
b) 1.3 x 10-3
c) 1.60 x 10-2
d) 1.6 x 10-2
b) 1.3 x 10-3
How many electrons are in the positive charged ion, N3-
10 electrons
Which of the following elements are diatomic molecules?
a) B
b) Mn
c) I
d) Ni
c) I
What is the empirical formula of the compound formed by a calcium and Chloride ion?
a) Cu2Cl
b) CaCl2
c) CuCl2
d) Ca2Cl3
b) CaCl2
In order for something to be considered matter, it must first have what?
Mass
The density of a cube is 2.16 g/cm3 and has a side length of 5.00 mm. What is the mass of the cube?
a) 0.270 g
b) 0.480 g
c) 0.367 g
d) 0.555 g
a) 0.270 g
The isotope Co-60 has how many protons, neutrons, and electrons?
27 protons, 33 Neutrons, 27 electrons
Metals tend to _____ electrons, which makes them known as _______?
lose, cations
What is the empirical formula for a compound formed by S2- and Zn2+
ZnS
Solids differ from liquid by ______. Gas differs from Solids and Liquids by ______.
Hint: think of composition of matter and its properties
Specific shape
Compressibility
*look at chart on slide 15 for review*
convert 5.0 km3 to ml
a) 5.0 x 10-15 ml
b) 4.74 x 10-10 ml
c) 5.0 x 10-20 ml
d) 4.74 x 10-6 ml
a) 5.0 x 10-15 ml
An element has the following natural abundances and isotopic masses: 90.92% abundance with 19.99 amu, 0.26% abundance with 20.99 amu, and 8.82% abundance with 21.99 amu. Calculate the average atomic mass of this element.
a) 20.16 amu
b) 30.27 amu
c) 22.88 amu
d) 19.99 amu
a)20.16 amu
Which of the following group of elements would you expect to behave similarly?
a) Neon and Fluorine
b) Magnesium and Sodium
c) Nitrogen and Potassium
d) Oxygen and Sulfur
d) Oxygen and Sulfur
What is the empirical formula for Sodium Sulfate?
Na2(SO4)