N/A - Exam Exam Answers

Which diagram represents a gas that has been ionized?

Which best describes a compound such as magnesium oxide?

Which can be categorized as a use of plasma in technology?

What is the percent by mass of magnesium sulfate in cap m g cap s cap o sub 4 ⋅ 7 cap h sub 2 cap o ? Use percent Element is equal to total mass of element in compound over molar mass of compound times 100

A teacher wants to perform a classroom demonstration that illustrates both chemical and physical changes. Which would be the best demonstration that she could use?

Which element would most likely have chemical properties similar to that of fluorine ( cap f )?

Which is a component of John Dalton’s atomic theory?

Ethylene, a gas found in nature, is commonly used to ripen bananas and other fruits. Which compound is ethylene?

When chemists convert ethene open paren cap c sub 2 cap h sub 2 close paren to ethanol open paren CH sub 3 CH sub 2 OH close paren , they have a mixture of the two gaseous substances. Why do chemists then lower the temperature of the mixture?

Which statement best compares the energy involved in melting with the energy involved in boiling for a given liquid?

What is the name of the ionic compound RbCl ?

Which element is likely to have a high thermal conductivity?

Which is a feature of a single replacement reaction?

Which statement best explains why different gases effuse at different rates?

A sample of ammonia reacts with oxygen as shown. 4 NH sub 3 g plus 5 cap o sub 2 g rightarrow 4 NO g plus 6 cap h sub 2 cap o g What is the limiting reactant if 4 point 0 g of NH sub 3 react with 8 point 0 g of oxygen?

A single atom of an element has 21 neutrons, 20 electrons, and 20 protons. Which element is it?

Consider the balanced equation. PCl sub 3 plus 3 cap h sub 2 cap o rightarrow cap h sub 3 PO sub 3 plus 3 HCl What is the percent yield of HCl if 42 point 0 g of HCl are produced from the reaction of 62 point 0 g of PCl sub 3 ? Use percent Yield is equal to Actual yield over Theoretical yield times 100

The properties of two elements are listed. Element Atomic radius (pm) Ionic radius (pm) First ionization energy (kJ/mol) Electron affinity (kJ/mol) Electronegativity Br 114 195 1140 negative 325 3 point 0 cap k 243 152.2 418 point 8 negative 48 point 4 0.82 Which prediction is supported by the information in the table?

Two students are given two different size blocks of the same substance and are instructed to determine the properties of the substance. Which statement describes a property that will be the same for both students?

Four substances are tested for different properties. The results of the tests are in the table. Substance Combustible Reactivity Solubility in water Solubility in ether Boiling point ( degree cap c ) W Yes Yes Soluble Insoluble 883 X Yes No Insoluble Insoluble 2,750 Y Yes No Insoluble Soluble 196 Z No Yes Soluble Soluble 98 Which substance is most likely an alkane?

What is the element Ar classified as in the periodic table?

Which synthetic and natural polymers can be used to make thread or rope?

An electron in a hydrogen atom moves from level 1 to level 4. The electron then drops from level 4 to level 2. Which statement describes the most likely result?

Which is true of transition metals when moving from left to right on the periodic table?

An element has five valence electrons available for bonding. This element is most likely which of these?

Which statement is part of Dalton's atomic theory?

Which compound contains both sigma and pi bonds?

Which statement explains how the bands in the crystal of a metal are like atomic orbitals?

What is the true ratio of atoms in a molecule or formula unit called?

In which orbitals would the valence electrons for carbon cap c be placed?

Which diagram shows electrons violating the Pauli exclusion principle?

Consider the word equation. calcium hydroxide plus hydrochloric acid rightarrow calcium chloride plus water Which is the corresponding formula equation?

Which is a characteristic of nuclear fission?

Kumar is producing the photoelectric effect by using red light. He wants to increase the energy of emitted electrons. Based on the research of Albert Einstein, what is the best way for him to do this?

Which statement best explains why the atomic theory developed efficiently?

Which is the formula for diarsenic pentoxide?

Which statement is true about crystal lattice energy?

Based on the information that is given, which atom in the table has the highest mass?

In which region are most particles moving the fastest?

The process shown in the image can best be described as a

What is the name of this hydrocarbon?

Which statement can be placed in the blank cell to make the information in the table accurate?

Which postulate of the kinetic-molecular theory best describes the event in the diagram?

Which substance most likely has the strongest intermolecular forces?

Elements that have complete valence electron shells are mostly found in the

The attractive force between these two molecules has most likely been produced by

Assuming the compound is dissolved in water, what is the formula for phosphorous acid?

Which model is useful in showing the reactivity of potassium?

Which best describes what is represented by images 1 and 2?