Cumulative Exam — Cumulative exam Answers

Consider the balanced equation below.N2H4 + 2H2O2 N2 + 4H2OWhat are the mole ratios of hydrazine (N2H4) to hydrogen peroxide (H2O2) and hydrazine to water?

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?

The expression below was formed by combining different gas laws. Which law was used to determine the relationship between the volume and the number of moles in this equation?

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?

A mixture of three noble gases has a total pressure of 1.25 atm. The individual pressures exerted by neon and argon are 0.68 atm and 0.35 atm, respectively. What is the partial pressure of the third gas, helium?Use .

The table below gives the numbers of protons, electrons, and neutrons in four atoms.AtomNumber of protonsNumber of electronsNumber of neutrons1393952240405033939544404051Based on the information that is given, which atom in the table has the highest mass?

Which of the following best describes a pair of elements that will form an ionic bond?

Which statement best explains why the atomic theory developed efficiently?

Consider the reaction below.2C6H14 + 19O2 12CO2 + 14H2OHow many moles of hexane (C6H14) must burn to form 18.4 mol of carbon dioxide?

The diagrams below represent the four states of matter. Diagram 1 Diagram 2 Diagram 3 Diagram 4Which diagram represents a gas that has been ionized?

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

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 task most likely involves a calculation that uses moles?

In which orbitals would the valence electrons for carbon (C) be placed?

Which compound contains both sigma and pi bonds?

What is produced when calcium reacts with fluorine in a synthesis reaction?Ca + F2 ________

Which best describes a compound such as magnesium oxide?

The chemical equation below shows the burning of magnesium (Mg) with oxygen (O2) to form magnesium oxide (MgO).2Mg + O2 2MgOThe molar mass of O2 is 32.0 g/mol. What mass, in grams, of O2 is required to react completely with 4.00 mol of Mg?

When a drawing of a circle made in the center of a piece of paper with a black marker gets wet, the marker bleeds, and as the water moves through the paper the ink separates into several colors. What method of separation does this describe?

The diagram below shows that the periodic table is divided into different blocks.Elements that have complete valence electron shells are mostly found in the