WorksheetsKimikaHusayan
Total questions: 33
Worksheet time: 22mins
The nucleus of an atom consists of ___________.
Electrons and neutrons
Electrons and protons
Protons and neutrons
The number of moles of solute present in 1 kg of a solvent is called its _______.
Molality
Molarity
Normality
The most electronegative element among the following is
Sodium
Bromine
Fluorine
What is an octet rule?
A rule that says that atoms like to have a full valence shell of eight electrons
A rule that says that eight electrons resides in the nucleus of an atom
A rule that says that atoms bond eight times with other atoms
An arrow that is used to represent resonance
Single headed arrow
Double headed arrow on both ends of the arrow
Double harpoons
The number 0.005436 has how many significant figures?
7
3
4
5
At room temperature, most elements are in which phase of matter?
solid
liquid
gas
plasma
The word atom is from a Greek word meaning:
small
indivisible
unseen
visible
The symbol Sb stands for stibnum or stibnite. What is the modern name of this element?
Arsenic
Antimony
Tin
Samarium
Of the following name/symbol combinations of elements, which one is WRONG?
uranium / U
sulfur / S
potassium / K
iron / I
Which statement is false about the First Law of Thermodynamics?
It states that energy cannot be created
It states that energy cannot be destroyed
It states that an object will not change its motion unless a force acts on it
Which of the ff. is the Boyles Law Equation?
PV = nRT
P1V1 = P2V2
V1/T1 = V2/T2
D = mP/RT
How many valence electrons does the element Nitrogen have?
4
3
5
6
Using the number of Lewis dots of Nitrogen, it can be a reference to ________ where it belongs.
Period
Configuration
Group
Race
Combination reaction always:
Use only one reactant
Form only one product
Require oxygen gas
The study of phenomena at very low temperatures is called:
heat transfer
morphology
crystallography
cryogenics
Water flows through a horizontal pipe at a constant volumetric rate. At a location where the cross sectional area decreases, the velocity of the fluid:
increases
decreases
stays the same
Which answer includes all the ff. that are chemical changes and not physical changes?
I. freezing of water
II. rusting of iron
III. dropping a piece of iron into hydrochloric acid (H2 is produced)
IV. burning a piece of wood
V. emission of light by a kerosene oil lamp
III and IV
II and V
I, II, III, IV, and V
II, III, IV, and V
When iron pyrite (FeS2) is heated in air, the process known as "roasting" forms sulfur dioxide and Iron(III) oxide. When the equation for this process is completed and balanced, using the smallest whole number coefficients, what is the coefficient for "O2"?
___ FeS2 + ___ O2 → ___ SO2 + ___ Fe2O3
2
4
7
11
Arrhenius defined an acid as:
a species that can donate a proton
a species that can accept a proton
a source of OH- ions in water
a source of H+ ions in water
In the Bronsted-Lowry system, a base is defined as:
a proton donor
a hydroxide donor
an electron-pair acceptor
a proton acceptor
Which of the following scientists was awarded the Nobel Prize in 1911 for the discovery of the radioactive elements, radium and polonium?
John Dalton
Marie Curie
Emil Fischer
Dmitri Mendeleev
Global climate change is being attributed to the atmospheric increase in what two gases produced by human activities?
oxygen and hydrogen
methane and carbon dioxide
ozone and methane
nitrous oxide and sulfur dioxide
What volume of 10.0 M H2SO4 is required to prepare 4.0 L of 0.50 M H2SO4?
0.20 L
0.40 L
0.50 L
1.0 L
Of the choices below, which one is not an ionic compound?
PCl5
MoCl6
RbCl
PbCl2
Balance the Equation:
___ NH4OH + ___ H3PO4 →
___(NH4)3PO4 + ___ H2O
(a)
How many milliliters of 0.200 M NH4OH are needed to react with 12.0 mL of 0.550 M FeCl3?
FeCl3 + 3NH4OH → Fe(OH)3 + 3NH4Cl
(a)
Calculate the average atomic mass of Sulfur if 95.00% of all Sulfur atoms have a mass of 31.972 amu, 0.76% has a mass of 32.971 amu and 4.22% have a mass of 33.967 amu.
(a)
Selenium, an element used in the manufacture of solar energy devices, forms an oxide that contains only one atom of selenium (per formula unit) and is 37.8% oxygen by mass. What is the molecular formula of the oxide?
SeO3
SeO2
Se2O
SeO
Solid sulfur and oxygen gas react to produce sulfur trioxide as shown below. In a particular experiment, 5.0 g of O2 are reacted with 6.0 g of S8.
S8 (s) + O2 (g) → SO3 (g)
If we assume complete consumption of the limiting reactant, what is the mass and identity of the reactant that still remains at the end of the reaction?
2.6 g S8 remains
2.6 g O2 remains
7.9 g S8 remains
8.34 g O2 remains
Temperature and melting point, have values that do not depend on the amount of sample.
Intensive Property
Extensive Property
Number of known elements as of 2020?
110
116
118
Which is the only metal that is liquid at room temperature?
Silver
Mercury
Gallium
