WorksheetsPhysical Science Jam - 8th Grade
Total questions: 35
Worksheet time: 48mins
Sugar molecules and water molecules are represented by circles of different patterns, as shown here. Which best represents sugar dissolved in water?
Which best describes a compound?
the simplest form of matter
an element that has changed state
a physical mixture of chemicals and elements
a chemical combination of two or more elements
The table shows the chemical formulas for several common substances. Which compound contains the most atoms?
ammonia
baking soda
sugar
water
Which is most likely to be a mixture?
substance formed when one atom combines with another atom of the same element
substance formed when one atom combines with an atom of another element
solution formed when one substance chemically combines with another
solution formed when one substance dissolves in another
When elements chemically combine, which best describes the resulting compound?
It has different ratios of atoms.
It has different types of matter.
It has the same properties as the uncombined elements.
It has different properties from the uncombined elements.
A substance contains two components joined by physical means. Which best describes the substance?
element
compound
mixture
molecule
The figure shows how information about a specific element is represented on the periodic table. What information does the symbol "B" give about the element?
It tells the element's atomic mass.
It tells the atomic density of the element.
It tells the chemical symbol of the element.
It tells the element's number of protons and electrons.
How are elements similar to those in the same group on the periodic table?
They have the same number of valence electrons.
They have the same number of electrons.
They have the same number of protons.
They have the same atomic mass.
Which element is in the same family as chlorine (Cl) and fluorine (F)?
(you may want to use a periodic table to answer this question)
hydrogen (H)
lithium (Li)
oxygen (O)
bromine (Br)
Sodium (Na), lithium (Li), and potassium (K) are grouped together in one column on the periodic table. Which property do they share?
(you may want to use a periodic table to answer this question)
soft texture
high reactivity
semiconductivity
gas at room temperature
Where on the periodic table is a metal element most likely found?
middle
bottom
left side
right side
Which best explains why the alkali metals are the most reactive group in the periodic table?
They are radioactive.
They have complete outer energy levels.
They have the highest atomic masses of any elements.
They have only one electron in their outer energy level.
Which is indicated if a gas forms when two or more substances are mixed?
physical change
chemical change
physical property
chemical property
Liquids placed in a beaker will settle in specific layers. Which physical property of matter does this illustrate?
density
polarity
solubility
malleability
Max combines baking soda and vinegar in a flask. Which is the most likely reason Max should place a balloon over the mouth of the flask before he mixes the two substances?
to prevent any gas formed as a product from escaping during the reaction
to prevent any liquid used as a reactant from escaping during the reaction
to prevent any powder used as a reactant from escaping during the reaction
to prevent any liquid formed as a product from escaping during the reaction
The table shows the procedure for an experiment. Which best describes the change that occurred?
physical change because the atoms rearranged to form a new substance
chemical change because dissolving a solid into a liquid cannot be reversed
chemical change because the state of the salt changed from solid to liquid when dissolved
physical change because the chemical properties of the salt and water remained the same
One-half cup of baking soda is placed inside a plastic bag containing one cup of vinegar. Which best describes the evidence that a chemical reaction is taking place?
The substance boils and changes state of matter.
Bubbles are created, and a new substance is formed.
The final result of the reaction is a vinegar and baking soda mixture
The vinegar and the baking soda remain unchanged after the reaction.
Which demonstrates a chemical change?
water + salt = saline solution
white sugar + clear acid = black solid
water + blue food coloring = blue solution
red food coloring + yellow food coloring = orange solution
The chemical equation shows only the reactants and one product. How many H atoms must be present in the second product that is formed?
1
2
3
4
Karsandra and Alex conducted an experiment where they heated water in a beaker on a hotplate. They recorded their results in the table here. Which of the following statements is true based on the results?
The law of conservation of matter was broken in this experiment because the mass of the water decreased after heating.
The law of conservation of matter was not broken because the water was heated in an open beaker, letting gases escape.
The law of conservation of matter was not broken because the mass before heating was greater than the mass after heating.
The law of conservation of matter was broken in this experiment because the water was heated in an open beaker, letting gases escape.
A student measures the mass of an apple before and after cutting it into four equal slices, as shown.
What is the mass of the apple slices?
25 g
50 g
100 g
125 g
Which best describes a chemical reaction applying the law of conservation of mass?
an equation which uses energy
an equation which does not use energy
a balanced equation in which the reactants and products are equal
an unbalanced equation in which the reactants and products are unequal
A 12-gram sample of magnesium (Mg) reacts with an 18-gram sample of sulfur (S) when heated. Magnesium sulfide (MgS), a crystalline material, is formed. What mass of MgS is most likely produced?
6 grams
30 grams
60 grams
216 grams
An experiment was conducted to test the law of conservation of mass. At the end of the experiment, only 82% of the mass of the initial reactants was present. The experiment was repeated three times with similar results. Which best explains why some of the mass was lost?
The mass escaped as a gas.
The mass transformed into a liquid.
The mass remained a part of the reactant.
The mass turned into a heavier chemical.
Which part of the atom has a negative charge and moves around the nucleus?
Proton
Neutron
Electron
Nucleus
A student is using the periodic table to draw models of atoms. They are asked to make a model of the element magnesium. How many protons should be placed in the nucleus of this model?
6 protons
12 protons
24 protons
36 protons
Where are protons and neutrons located in an atom?
Scattered throughout the atom
Inside the electron cloud
In the nucleus
On the outside shell
Mitch's science teacher asked the students to draw a model of a hydrogen atom with a mass of 1. Mitch drew the model to the left.
Is Mitch’s model correct?
The model is correct because hydrogen only has one neutron.
The model is incorrect because hydrogen only contains one proton and one electron.
The model is incorrect because Mitch placed the proton and electron in the wrong location.
The model is correct because there are the same amount of neutrons, protons, and electrons.
Which subatomic particle has no charge and is found in the nucleus?
Proton
Electron
Ion
Neutron
Why are models used to show atomic structure?
Atoms are too small to see, and models help represent their parts.
Atoms are not made of smaller parts.
All atoms are exactly the same size and shape.
Atoms can be seen under a microscope easily.
During an experiment, a scientist studies three different samples. Which statement best classifies these substances?
Sample A: Made up of only copper (Cu) atoms
Sample B: Made up of water molecules (H₂O)
Sample C: A mix of sugar, salt, and sand, all visible and not chemically bonded
Sample A is a compound, Sample B is a mixture, and Sample C is an element.
Sample A is an element, Sample B is a compound, and Sample C is a mixture.
Sample A is a mixture, Sample B is an element, and Sample C is a compound.
Sample A is a compound, Sample B is an element, and Sample C is a mixture.
The chart shows the composition of an unknown atom. Which atom is described in the chart?
sulfur
silicon
nitrogen
phosphorous
A scientist discovers a new element and places it in Group 18 on the periodic table. Based on its location, what is the most likely property of this element?
It reacts violently with water.
It is a poor conductor of electricity and does not form compounds easily.
It is a metal that is highly malleable.
It is a liquid that easily forms bonds with other elements.
While making pancakes, Jamie notices that the liquid batter thickens as it is heated, bubbles form on the surface, and the pancake changes from light yellow to golden brown. Which of the following best explains what happens during this process?
The pancake batter undergoes a physical change because heat causes the water in the batter to evaporate.
The pancake batter undergoes a chemical change because new substances are formed as the ingredients react.
The pancake batter undergoes a physical change because the shape of the pancake changes.
The pancake batter undergoes a chemical change because the temperature increases, but the composition remains the same.
A stack of newspapers is burned completely to ash in a laboratory. How does the resulting mass relate to the initial mass of the stack of newspapers?
The mass of the gases and the ash should equal the mass of the initial stack of newspapers.
The mass of the gases and the ash should be one-fourth the mass of the initial stack of newspapers.
The mass of the gases and the ash should be one-half the mass of the initial stack of newspapers.
The mass of the gases and the ash should be double the mass of the initial stack of newspapers.
