Chemistry – Flashcards

Unlock all answers in this set

Unlock answers
question
Xylene, a compound with the formula C8H10, is composed of
answer
eight atoms of carbon and ten atoms of hydrogen.
question
When Phosphorous-30 loses a positron what is the product of this radioactive decay?
answer
30/14Si
question
Which of the following observations demonstrates that a solid sample is a compound?
answer
It cannot be broken down into simpler substances by physical methods.
question
Calculate the density of cyclohexane if a 50.0 g sample has a volume of 64.3 mL.
answer
0.778 g/mL
question
Atoms of 35/17 Cl contain ________ protons and ________ electrons.
answer
17,17
question
What is the missing reactant in the reaction shown?
answer
4/2 He
question
A chemical reaction occurs when
answer
a substance's structure is altered.
question
Which of the following combinations represents only alkali metals? I. Li II. Ba III. Rb IV. Ca
answer
I + IIII
question
Round the following number to 3 significant figures: 546.85 grams.
answer
547
question
Which nuclear reaction is an example of positron emission?
answer
22/11Na-->22/10 Ne+0/+1B
question
Elements in the Periodic Table are arranged according to
answer
Atomic Number
question
Which of the following is an element?
answer
Sodium
question
What is the chemical symbol for calcium?
answer
Ca
question
The mass number of Br-81 is
answer
81
question
The amount of matter in an object is its
answer
Mass
question
How many O atoms are in the formula unit GaO(NO3)2?
answer
7
question
Which elements all belong in the same group?
answer
F, Cl, Br
question
What is the chemical symbol for copper?
answer
Cu
question
Which is the best description of an alpha particle?
answer
charge +2; mass of 4 amu; low penetrating power
question
Which product is formed by alpha emission from gold-185? The atomic number of gold is 79.
answer
181/77Ir
question
Suppose that element Z has the following properties: a. noncombustible b. unreactive c. colorless, odorless gas at room temperature d. nonconductor of electricity Element Z could be classified as a ________ and will be found on the ________ of the Periodic Table.
answer
non-metal; right
question
Where is most of the mass of an atom concentrated?
answer
Nucleus
question
The symbol of the element with 23 protons is
answer
V
question
Element Z has the following properties: a. silvery-white solid at room temperature b. malleable c. used as a catalyst d. conducts electricity Element Z can be classified as a ________ and will be found on the ________ of the Periodic Table.
answer
Metal; left
question
If gasoline sells for 95.4 cents per liter, what is its cost on a per gallon basis? 1 L = 1.06 q
answer
$3.60
question
What is the specific gravity of a liquid sample with a mass of 35.0 g and a volume of 14.00 mL?
answer
2.5
question
If you bake a pizza at 450°F, what are the Celsius and Kelvin equivalents of this temperature?
answer
Since 32 is in Fahrenheit, you need to subtract the 32 from 450°F *before* you divide by 1.8. Then you need to use only 2 sig figs
question
The half life of a specific technetium isotope is 6 hours. How much of an 192 mg sample will have decayed after 30 hours
answer
Your math is correct - 6 mg remain - but the question says how much has *decayed*. That would be 186 mg.
question
Grain alcohol has a density of about 6.6 pounds/gallon. What is the density in g/mL?
answer
...
Get an explanation on any task
Get unstuck with the help of our AI assistant in seconds
New