PLATO Course Chemistry, Semester A,
Unit 1 Atoms and Elements
_______1______-is the use of reliable knowledge for a realistic cause.
_______2______is the observe of the natural global thru commentary and experimentation. -
ANS-1. NOT hypothesis
2. Science
A 46.9 gram pattern of a substance has a volume of about three.5 centimeters3. It is stable at a
room temperature of 23ºC. Out of the four materials whose houses are given, that is the most
probable identity of this substance? - ANS-hafnium
A certain atom has 22 protons and 19 electrons. This atom loses an electron. The net rate at the
atom is now_____1____. If this identical atom with 22 protons and 19 electrons had been to
gain 3 electrons, the internet charge on the atom would be ________2________. - ANS-1. NOT
1+
2. NOT -three
A certain pattern of a liquid has a mass of 42 grams and a extent of 35 centimeters^ three. What
is the density of the liquid? - ANS-The density of the liquid is 1.2 grams/centimeter ^3
A jar includes a positive substance. Which commentary might show that the substance have to
be either a strong or a liquid? - ANS-NOT The substance has each mass and extent.
A steel atom loses electrons from its outermost power level and acquires a______1____ fee.
These electrons be a part of a nonmetal atom. The ionic compound shaped because of this
transfer of electrons is electrically ___2_____ - ANS-1. Positive
2.Neutral
A scientist executed numerous unique procedures, every of which induced a change in matter.
Select each technique that is possibly a chemical exchange. - ANS-Bubbles have been
produced when iron become placed in acid.
Two liquids were blended, and a solid regarded.
A white substance grew to become blue whilst water became added.
An atom has nine electrons and nine protons at the begin. If it loses 2 electrons, the net fee at
the atom will be_____1____. If the atom as a substitute gains four electrons, the internet price
could be _____2_____ - ANS-1. 2+
2.Four-
An element belongs to organization 17 of the periodic table. This element is maximum possibly
a ____1______. A strong sample of this detail might have a _______2______ appearance. -
ANS-1. Nonmetal
2. Dull
Arrange the factors so as of increasing electronegativity. Use the periodic table that will help you
arrange the elements. - ANS-K<Mg<P<O
, Calculate the density of the substance. - ANS-A sample of a substance has a mass of 4.2
grams and a volume of 6 milliliters. The density of this substance is __.7__grams/milliliter.
Classify each substance as a pure substance or a mixture. - ANS-PURE SUBSTANCE
copper, which consists of only one kind of atom
carbon dioxide, which has two atoms of oxygen for each atom of carbon
table salt, which can be separated into sodium and chlorine only by chemical processes
MIXTURE
seawater, which can be purified by filtering it
a solution of sugar dissolved in water
Complete the following statements to describe solids, liquids, and gases. Select the correct
answer from each drop-down menu. - ANS-A solid __HAS__ a definite volume and __HAS__ a
definite shape. A liquid __HAS__ a definite volume and __does not have__ a definite shape. A
gas __does not have__ a definite volume and __does not have__ a definite shape.
Consider an atom that has an electron in an excited state. The electron falls to a lower energy
level. What effect does that have on the electron? - ANS-The electron releases energy in the
form of light.
Electrons are transferred from atoms of___1__to atoms of ___2___. This transfer makes the
sodium atoms ____3____ and the phosphorus atoms __4___. As a result, the sodium and
phosphorus atoms strongly ___5__ each other. - ANS-1. Sodium
2.Phosphorus
3.Positive
4. Negative
5.Attract
How was Rutherford's gold foil experiment inconsistent with the plum pudding model of the
atom? - ANS-NOT The model could not explain why the electrons in the atom would be evenly
spaced.
Identify an element on the periodic table that is chemically similar to boron (B). - ANS-Gallium
(Ga)
Identify an element on the periodic table that is chemically similar to neon (Ne). - ANS-Helium
(He)
Identify each section of the periodic table.
Metals - ANS-yellow: metalloids
red: non metals
blue: metals
Identify the apparatus on the table that is best suited for a chemist to measure the volume of a
liquid. - ANS-The graduated cylinder
Identify the type of scientific knowledge represented by each statement. - ANS-If a certain piece
of metal is cooled, it will conduct electricity better.------->speculation
Unit 1 Atoms and Elements
_______1______-is the use of reliable knowledge for a realistic cause.
_______2______is the observe of the natural global thru commentary and experimentation. -
ANS-1. NOT hypothesis
2. Science
A 46.9 gram pattern of a substance has a volume of about three.5 centimeters3. It is stable at a
room temperature of 23ºC. Out of the four materials whose houses are given, that is the most
probable identity of this substance? - ANS-hafnium
A certain atom has 22 protons and 19 electrons. This atom loses an electron. The net rate at the
atom is now_____1____. If this identical atom with 22 protons and 19 electrons had been to
gain 3 electrons, the internet charge on the atom would be ________2________. - ANS-1. NOT
1+
2. NOT -three
A certain pattern of a liquid has a mass of 42 grams and a extent of 35 centimeters^ three. What
is the density of the liquid? - ANS-The density of the liquid is 1.2 grams/centimeter ^3
A jar includes a positive substance. Which commentary might show that the substance have to
be either a strong or a liquid? - ANS-NOT The substance has each mass and extent.
A steel atom loses electrons from its outermost power level and acquires a______1____ fee.
These electrons be a part of a nonmetal atom. The ionic compound shaped because of this
transfer of electrons is electrically ___2_____ - ANS-1. Positive
2.Neutral
A scientist executed numerous unique procedures, every of which induced a change in matter.
Select each technique that is possibly a chemical exchange. - ANS-Bubbles have been
produced when iron become placed in acid.
Two liquids were blended, and a solid regarded.
A white substance grew to become blue whilst water became added.
An atom has nine electrons and nine protons at the begin. If it loses 2 electrons, the net fee at
the atom will be_____1____. If the atom as a substitute gains four electrons, the internet price
could be _____2_____ - ANS-1. 2+
2.Four-
An element belongs to organization 17 of the periodic table. This element is maximum possibly
a ____1______. A strong sample of this detail might have a _______2______ appearance. -
ANS-1. Nonmetal
2. Dull
Arrange the factors so as of increasing electronegativity. Use the periodic table that will help you
arrange the elements. - ANS-K<Mg<P<O
, Calculate the density of the substance. - ANS-A sample of a substance has a mass of 4.2
grams and a volume of 6 milliliters. The density of this substance is __.7__grams/milliliter.
Classify each substance as a pure substance or a mixture. - ANS-PURE SUBSTANCE
copper, which consists of only one kind of atom
carbon dioxide, which has two atoms of oxygen for each atom of carbon
table salt, which can be separated into sodium and chlorine only by chemical processes
MIXTURE
seawater, which can be purified by filtering it
a solution of sugar dissolved in water
Complete the following statements to describe solids, liquids, and gases. Select the correct
answer from each drop-down menu. - ANS-A solid __HAS__ a definite volume and __HAS__ a
definite shape. A liquid __HAS__ a definite volume and __does not have__ a definite shape. A
gas __does not have__ a definite volume and __does not have__ a definite shape.
Consider an atom that has an electron in an excited state. The electron falls to a lower energy
level. What effect does that have on the electron? - ANS-The electron releases energy in the
form of light.
Electrons are transferred from atoms of___1__to atoms of ___2___. This transfer makes the
sodium atoms ____3____ and the phosphorus atoms __4___. As a result, the sodium and
phosphorus atoms strongly ___5__ each other. - ANS-1. Sodium
2.Phosphorus
3.Positive
4. Negative
5.Attract
How was Rutherford's gold foil experiment inconsistent with the plum pudding model of the
atom? - ANS-NOT The model could not explain why the electrons in the atom would be evenly
spaced.
Identify an element on the periodic table that is chemically similar to boron (B). - ANS-Gallium
(Ga)
Identify an element on the periodic table that is chemically similar to neon (Ne). - ANS-Helium
(He)
Identify each section of the periodic table.
Metals - ANS-yellow: metalloids
red: non metals
blue: metals
Identify the apparatus on the table that is best suited for a chemist to measure the volume of a
liquid. - ANS-The graduated cylinder
Identify the type of scientific knowledge represented by each statement. - ANS-If a certain piece
of metal is cooled, it will conduct electricity better.------->speculation
