WorksheetsRC
Total questions: 15
Worksheet time: 15mins
What does the Law of Conservation of Mass state?
Matter cannot be gained or lost in a chemical reaction.
Matter can only be lost in a chemical reaction.
Matter can only be gained in a chemical reaction.
Matter can be gained and lost in a chemical reaction.
A teacher is demonstrating physical and chemical changes to her class. Which action should she use to demonstrate a chemical change?
cutting a piece of paper
folding a piece of paper
tearing a piece of paper
burning a piece of paper
Which of the following could be the chemical formula for sulfuric acid (shown in the picture)? (8.5D)
HSO
HSO4
H2SO4
HS2O4
A student observes some sugar as it is heated and burns. The student concludes that a chemical reaction has occurred. Which of the following observations about the burning sugar provides evidence of a chemical reaction? (8.5E)
Heat is added to the sugar crystals.
The sugar melts and becomes a liquid.
The temperature of the sugar increases.
Gas is produced as the sugar turns black.
Coal contains carbon and other elements. Carbon dioxide forms when coal burns in the presence of oxygen. Which of these is the best evidence that a chemical reaction occurs when coal burns?
The shape of the coal changes
Oxygen is present
A new substance is produced
Coal is made up of more than one element
Four students performed four different investigations by combining different substances. Which of the observations is most indicative of a chemical reaction?
investigation 1
investigation 2
investigation 3
investigation 4
You know that a chemical reaction is occurring here because you see __________________ . (Pick 3)
purple color
smoke
ice formation
fire
a yellow precipitate
Which of the following describes a precipitate?
a liquid forms when a block of metal is heated
a solid forms when one liquid is poured into another
a gas forms when a solid is placed in a liquid
bubbles form when an acid is poured on a rock
Which pair of properties describes the elements in Group 18?
They are chemically stable and liquid at room temperature.
They have eight valence electrons and are flammable.
They are magnetic and boil at low temperatures.
They are gaseous at room temperature and chemically stable.
A student is studying Calcium (Ca), a highly reactive element that humans need for strong bones. Which characteristics of calcium is most closely related to its chemical reactivity?
The 20 protons in each atom of calcium
The density of calcium which is 1.54 g/cm3
The atomic mass of calcium which is 40.078 amu
The 2 valence electrons in each atom of calcium
The model of the periodic table in the illustration shows the location of four elements. A student is asked to identify an element that is a pale yellow brittle solid that does not conduct electricity. At which location in this periodic table would the element most likely be found?
1
2
3
4
A student is studying the ways different elements are similar to one another. The illustration contains diagrams of atoms from four different elements. Which two atoms are of elements in the same group in the periodic table?
Atom 1 and Atom 2
Atom 1 and Atom 4
Atom 2 and Atom 3
Atom 3 and Atom 4
RC
A) RC circuit is a type of electrical circuit that consists of a resistor and a capacitor.
B) RC circuit is a type of electrical circuit that consists of a resistor and a coil.
C) RC circuit is a type of electrical circuit that consists of a resistor and a conductor.
D) RC circuit is a type of electrical circuit that consists of a resistor and a converter.
RC
A) The time constant of an RC circuit is the product of the resistance and capacitance.
B) The time constant of an RC circuit is the sum of the resistance and capacitance.
C) The time constant of an RC circuit is the difference between the resistance and capacitance.
D) The time constant of an RC circuit is the ratio of the resistance to capacitance.
RC
A) In an RC circuit, the voltage across the capacitor increases exponentially with time when charging.
B) In an RC circuit, the voltage across the capacitor decreases linearly with time when charging.
C) In an RC circuit, the voltage across the capacitor remains constant with time when charging.
D) In an RC circuit, the voltage across the capacitor decreases exponentially with time when charging.
