Science Quiz: Weight, Changes, and Molecules

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

How is the weight of an object influenced when the gravitational force on the object is increased?

  • The weight increases (correct)
  • The weight decreases
  • It depends on the size of the object
  • The weight remains the same

The weight of an object is?

  • A measure of the object's density
  • None of the above
  • A measure of the gravitational force pulling the object toward the earth (correct)
  • The mass of the object multiplied by its volume

The fact that gold does not corrode is a?

  • Physical property
  • Chemical change
  • Chemical property (correct)
  • None of the above

Which of the following represents a physical change in matter?

<p>A substance solidifies at 443K (C)</p> Signup and view all the answers

The melting of ice to liquid water is correctly classified as?

<p>A physical change (B)</p> Signup and view all the answers

Which of the following is a chemical property of matter?

<p>Flammability (D)</p> Signup and view all the answers

As two clear liquid solutions are added together, a red solid forms. This change is most likely?

<p>A chemical change (B)</p> Signup and view all the answers

Which of the following substances are composed of heteroatomic molecules?

<p>Water (C)</p> Signup and view all the answers

A molecule represented by O-O-O must be classified as?

<p>Homoatomic and polyatomic (A)</p> Signup and view all the answers

Which of the following terms correctly applies to a molecule of CO2?

<p>Triatomic, heteroatomic (C)</p> Signup and view all the answers

Table salt, NaCl is best classified as a(n):

<p>Compound (B)</p> Signup and view all the answers

Homoatomic pure substances are known as:

<p>Elements (D)</p> Signup and view all the answers

After heating, a pure substance, A, is found to produce both B and C. What can be said about the substance A?

<p>It is a compound</p> Signup and view all the answers

Which of the following is an example of a homogeneous mixture?

<p>NaOH solution (B)</p> Signup and view all the answers

The basic unit of length in the metric system is the:

<p>Meter (A)</p> Signup and view all the answers

Why is CaO the symbol for calcium oxide instead of Cao?

<p>A capital letter means a new symbol</p> Signup and view all the answers

What is the meaning of the two in ethyl alcohol, C2H5OH?

<p>There are two carbon atoms per molecule of ethyl alcohol</p> Signup and view all the answers

A molecular formula:

<p>Is represented using the symbols of the elements in the formula</p> Signup and view all the answers

What is meant by carbon-12?

<p>The carbon atom has a relative mass of approximately 12 amu</p> Signup and view all the answers

Refer to a periodic table and tell how many helium atoms (He) would be needed to get close to the same mass as an average oxygen atom (O)?

<p>Four</p> Signup and view all the answers

Determine the molecular weight of hydrogen peroxide, H2O2 in u.

<p>34.02</p> Signup and view all the answers

Using whole numbers, determine the molecular weight of calcium hydroxide, Ca(OH)2.

<p>74</p> Signup and view all the answers

Which of the following carries a negative charge?

<p>An electron</p> Signup and view all the answers

Which of the following is located in the nucleus of an atom?

<p>Protons and neutrons (D)</p> Signup and view all the answers

Isotopes differ from each other in what way?

<p>They have different numbers of neutrons in the nucleus</p> Signup and view all the answers

The formula for dinitrogen monoxide is N2O. If a sample of the oxide was found to contain 0.0800 g of oxygen, how many grams of nitrogen would it contain?

<p>0.140</p> Signup and view all the answers

What is the number of hydrogen atoms in a 18.016 gram sample of water?

<p>1.204 x 10^24</p> Signup and view all the answers

What is the symbol for bromine?

<p>Br</p> Signup and view all the answers

What is the number of moles of water in one liter of water if one gram of water takes up one milliliter of space?

<p>55.6</p> Signup and view all the answers

How many hydrogen atoms are in 1.00 mole of NH3?

<p>18.1 x 10^23</p> Signup and view all the answers

Which of the following distinguishing electron configurations is characteristic of noble gases?

<p>np^6 (C)</p> Signup and view all the answers

Which of the following would cause a calcium atom (Ca) to achieve a noble gas configuration?

<p>Lose two electrons (B)</p> Signup and view all the answers

What is the formula weight of Ca(OH)2?

<p>74.1 u</p> Signup and view all the answers

Which of the following has a noble gas electronic configuration?

<p>Both A and B (D)</p> Signup and view all the answers

When magnesium forms an ion, it would be represented as:

<p>Mg^2+</p> Signup and view all the answers

Which of the following electronic changes will cause a Group VA (15) element to achieve a noble gas configuration?

<p>Gain three electrons (A)</p> Signup and view all the answers

The ionic compound that forms between magnesium (Mg) and oxygen (O) has the formula:

<p>MgO</p> Signup and view all the answers

When an ionic compound forms between sodium (Na) and bromine (Br) atoms, it is true that:

<p>A sodium atom donates an electron to a bromine anion (C)</p> Signup and view all the answers

The correct name for CeS is:

<p>Cerium sulfide</p> Signup and view all the answers

The rigid three-dimensional arrangement assumed by the ions of ionic compounds is called a:

<p>Crystal lattice</p> Signup and view all the answers

Which of the following would you expect to be the most polar molecule?

<p>H2S (A)</p> Signup and view all the answers

Which of the following is a correct electron dot formula for a group IIIA (13) element M?

<p>@M@</p> Signup and view all the answers

Which type of intermolecular forces leads to compounds with the lowest melting points?

<p>Dispersion forces (A)</p> Signup and view all the answers

The correct name for K2SO4 is:

<p>Potassium sulfate</p> Signup and view all the answers

A polar molecule must have:

<p>A positive and a negative end (B)</p> Signup and view all the answers

The correct name for KHPO4 is:

<p>Potassium hydrogen phosphate</p> Signup and view all the answers

Which of the following would be a polar molecule?

<p>HCl (B)</p> Signup and view all the answers

What property of a liquid such as mercury is used in a liquid-in-glass thermometer?

<p>Thermal expansion</p> Signup and view all the answers

A gas sample is collected in a balloon. What happens to the density of the gas sample as the sample is heated?

<p>Decreases</p> Signup and view all the answers

Potential energy resulting from the attraction of particles:

<p>More than one response is correct (C)</p> Signup and view all the answers

How does the kinetic energy of a particle change if the particle's velocity is increased by a factor of 3?

<p>Kinetic energy increases by a factor of 9</p> Signup and view all the answers

Cohesive forces in matter are related to

<p>Potential energy from particle attractions</p> Signup and view all the answers

High density is characteristic of which state of matter?

<p>More than one response is correct (C)</p> Signup and view all the answers

Definite shape is a characteristic of which state of matter?

<p>Solid (A)</p> Signup and view all the answers

Small compressibility is a characteristic of which state of matter?

<p>More than one response is correct (B)</p> Signup and view all the answers

Convert a temperature of 45 degrees Celsius into Kelvins

<p>318K</p> Signup and view all the answers

Increasing the pressure on a gas at a constant temperature does what to the volume of the gas?

<p>Decreases (A)</p> Signup and view all the answers

2500 liters of oxygen gas is produced at 1.00 atm of pressure. It is to be compressed and stored in a 20.0 liter cylinder. If temperature is constant, calculate the pressure of the oxygen in the cylinder.

<p>125 atm</p> Signup and view all the answers

A 5.00 liter sample of gas measured at 27.0 degrees Celsius and 1.25 atm of pressure has a mass of 10.13 g. What is the molecular weight of the gas in u?

<p>39.9</p> Signup and view all the answers

The force resulting from particle motion is referred to as:

<p>Disruptive forces</p> Signup and view all the answers

Near room temperature, air has a density of 1.18 x 10^-3 g/mL. What volume will 30.77 g of air occupy?

<p>2.61 x 10^4 mL</p> Signup and view all the answers

Which of the following correctly arranges the physical states of matter (gas -g, solid -s, liquid - l) in order of increasing energy of the particles (lowest to highest)?

<p>s &lt; l &lt; g (C)</p> Signup and view all the answers

In an exergonic process, the system:

<p>Loses energy</p> Signup and view all the answers

At 20 degrees Celsius, a sample of solid spontaneously sublimes to a gas. This change in state is accompanied by which of the following changes in the solid sample?

<p>Entropy and energy increase</p> Signup and view all the answers

The concept of entropy:

<p>Is employed as an indicator of disorder in a system</p> Signup and view all the answers

Which of the following interpretations of the spontaneous chemical reaction is correct?

<p>The entropy on the right of the equation is greater than that on the left</p> Signup and view all the answers

Most automobiles function by burning gasoline by a process similar to the equation in which octane is burned: C8H18 + O2 ---> CO2 + H20 + heat (not balanced)

<p>It explains why a car stops running when there is no gas in the fuel tank</p> Signup and view all the answers

Which of the following states of matter generally has the lowest entropy?

<p>Crystalline solid (A)</p> Signup and view all the answers

Catalytic action is:

<p>Directly opposed by inhibitors</p> Signup and view all the answers

Sulfur reacts with oxygen to produce sulfur dioxide, but only if the high activation energy is supplied. Which condition will lower the activation energy the most?

<p>Using a catalyst</p> Signup and view all the answers

The energy required to start some spontaneous processes is called:

<p>Activation energy</p> Signup and view all the answers

Which of the following will influence all reaction rates?

<p>More than one response is correct (B)</p> Signup and view all the answers

Homogeneous catalysts are thought to function by:

<p>Lowering activation energy of a reaction</p> Signup and view all the answers

Flashcards

Weight

Measure of gravitational force pulling an object toward Earth.

Chemical Property

Characteristic that determines how a substance can change into another substance.

Physical Change

Change that alters the form of a substance but not its identity.

Flammability

Chemical property that refers to a substance's ability to burn.

Signup and view all the flashcards

Heteroatomic Molecule

Molecule containing different types of atoms.

Signup and view all the flashcards

Homoatomic Molecule

Molecule made up of the same type of atoms.

Signup and view all the flashcards

Triatomic Molecule

Molecule consisting of three atoms.

Signup and view all the flashcards

Compound

Pure substance formed from chemical combinations of two or more elements.

Signup and view all the flashcards

Homogeneous Mixture

A mixture with a uniform composition throughout.

Signup and view all the flashcards

Meter

Basic unit of length in the metric system.

Signup and view all the flashcards

Molecular Weight

Mass of a molecule, typically expressed in atomic mass units (u).

Signup and view all the flashcards

Mole

Amount of substance containing as many entities as there are atoms in 12 g of carbon-12.

Signup and view all the flashcards

Electron Charge

Electrons carry a negative charge.

Signup and view all the flashcards

Isotope

Variants of an element with the same number of protons but different numbers of neutrons.

Signup and view all the flashcards

Exothermic Process

A reaction that releases energy, usually as heat.

Signup and view all the flashcards

Catalysts

Substances that lower the activation energy of a reaction.

Signup and view all the flashcards

Solid Matter

Has a definite shape and high density compared to liquids and gases.

Signup and view all the flashcards

States of Matter

Different forms in which matter can exist: solid, liquid, gas.

Signup and view all the flashcards

Noble Gas Configuration

Stable electron arrangement characteristic of noble gases, usually np^6.

Signup and view all the flashcards

Electron Transfer

Process by which atoms gain or lose electrons to achieve stability.

Signup and view all the flashcards

Reactions

Processes in which substances interact to form new substances.

Signup and view all the flashcards

Density

Mass per unit volume of a substance.

Signup and view all the flashcards

Entropy

Measure of disorder in a system; higher entropy means more disorder.

Signup and view all the flashcards

Solidification

Physical change where a substance becomes solid from a liquid.

Signup and view all the flashcards

Chemical Change

A transformation that alters the identity and composition of a substance.

Signup and view all the flashcards

Activation Energy

Minimum energy required to start a chemical reaction.

Signup and view all the flashcards

Molecular Composition

Arrangement and types of atoms in a molecule.

Signup and view all the flashcards

Gas Under Pressure

Demonstrates that volume decreases when pressure increases.

Signup and view all the flashcards

Catalytic Action

Influence of a catalyst on the rates of a chemical reaction.

Signup and view all the flashcards

Study Notes

Weight and Gravitation

  • Weight increases with an increase in gravitational force on an object.
  • Weight is defined as the measure of the gravitational force pulling an object toward the Earth.

Chemical and Physical Changes

  • Gold’s resistance to corrosion is a chemical property.
  • A physical change is illustrated when a substance solidifies, such as at 443K.
  • Melting ice to liquid water is classified as a physical change.
  • Flammability is identified as a chemical property of matter.
  • The formation of a solid from two clear liquids indicates a chemical change.

Molecular Composition

  • Heteroatomic molecules include substances like water.
  • A molecule represented as O-O-O is classified as homoatomic and polyatomic.
  • Carbon dioxide (CO2) is triatomic and heteroatomic.
  • Table salt (NaCl) is classified as a compound, while homoatomic pure substances are known as elements.

Compounds and Mixtures

  • A pure substance that produces more than one substance upon heating is a compound.
  • An example of a homogeneous mixture is a sodium hydroxide solution.

Metric System and Chemical Formula

  • The basic unit of length in the metric system is the meter.
  • The formula for ethyl alcohol (C2H5OH) indicates two carbon atoms per molecule.

Molecular Weight and Moles

  • Molecular weight of hydrogen peroxide (H2O2) is approximately 34.02 u.
  • Calcium hydroxide (Ca(OH)2) has a molecular weight of 74 u.
  • One liter of water contains about 55.6 moles, and a sample of water weighing 18.016 grams has 1.204 x 10^24 hydrogen atoms.

Atomic Structure

  • Electrons carry a negative charge, while protons and neutrons are located in the nucleus of an atom.
  • Isotopes differ in the number of neutrons within their nucleus.

Reactions and Stoichiometry

  • The formula for dinitrogen monoxide (N2O) can be used to calculate nitrogen content based on oxygen mass.
  • Various conversions can determine gas properties such as density and molecular weight under specific conditions.

States of Matter and Energy

  • Experiments involving gas under pressure show that volume decreases with increased pressure.
  • The density of near room temperature air is approximately 1.18 x 10^-3 g/mL.

Chemical Kinetics and Thermodynamics

  • In exothermic processes, the system loses energy, while entropy is an indicator of system disorder.
  • Catalysts lower activation energy, facilitating reactions; inhibitors oppose this effect.

Properties of Matter

  • Solid matter has a definite shape and high density.
  • The melting states of matter are organized as solid < liquid < gas in terms of increasing particle energy.

Electronic Configurations and Ion Formation

  • Noble gases exhibit an electronic configuration characterized by np^6.
  • Atoms achieve noble gas configuration by electron transfer, such as calcium losing two electrons or group VA elements gaining three.

Chemical Reactions and Catalytic Action

  • The addition of catalysts will influence reaction rates and lower the activation energy necessary for reactions to occur.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser