Which one is the best description of a chemical reaction? A.) mixing two substances B.) the combustion of a substance C.) forming or breaking bonds D.) the decomposition of particles
A toy boat is floating in a large metal bucket. If you build a fire under the bucket, how the heat will transfer from the fire to the boat? A. Water molecules in the bucket will transfer the heat. B. Metal molecules of the bucket will transfer the heat. C. Surrounding air molecules will transfer the heat.
Which of the following describes a condition in which an individual would not hear an echo? A. An individual is standing 30 meters in front of the reflecting surface. B. The reflecting source is approximately 21.5 meters from the individual. C. An individual is standing in the range of the sound waves coming from the original sound source as well as the reflected waves. D. A sound wave reaches the ear and the reflected wave reaches the ear less than 0.1 second later.
Which of the following is not a common hydrate a epsom salt b borax c sugar d alum i belive the answer is sugar
A _____ change occurs when a substance changes phase. physical chemical nuclear user: the latent heat of vaporization of ethanol is 200 calories/gram. this means that _____. about 200 calories of heat must be added to 1 gram of ethanol to change its temperature about 200 calories of heat must be added to 1 gram of ethanol to convert it from a solid to a liquid about 200 calories of heat must be added to 1 gram of ethanol to convert it from a liquid to a gas
What are the two causes of density in deep current waters? a. Salinity (how much salt) of the water and high temperatures c. Oxygen content of the water and high temperatures . b. Salinity (how much salt) of the water and low temperatures d. Oxygen content of the water and low temperatures
Which of the following reactions results in a decrease in entropy? (2 points) Question 17 options: 1) 6CO2 (g) + 6H2O (l) yields C6H12O6 (s) + 6O2 (g) 2) 2NH3 (g) yields N2 (g) + 3H2 (g) 3) N2O4 (g) yields 2NO2 (g) 4) 2H2O2 (aq) yields 2H2O (l) + O2 (g)
Iron reacts with oxygen to form iron oxide (rust). Whichof the statements below best describes this statement? A. Iron oxide is the liquid state of iron. B. Iron oxide is the gaseous state of iron. C. Iron oxide is formed by rearranging atoms. D. Iron oxide is made up of only iron atoms.
Methane reacts with oxygen to produce carbon dioxide and water,What are the products? A. methane and water. B. oxygen and carbon dioxide. C. methane and oxygen. D. carbon dioxide and water.
Which career is most concerned with the study of radioactive isotopes? biochemist nuclear chemist organic chemist nuclear engineer
Which of the following would be the least reliable source of scientific information? newspaper scientific journal government internet site science textbook
Deterioration of buildings, bridges, and other structures through the rusting of iron costs millions of dollars every day. although the actual process also requires water, a simplified equation (with rust shown as fe2o3) is: 4 fe(s) + 3 o2(g) → 2 fe2o3(s) δhrxn = −1.65 × 103 kj (a) what is the δhrxn when 0.250 kg of iron rusts?
Which is a correct comparison between the modern quantum model and John Dalton’s model of the atom? A.The modern model is not as widely accepted by scientists as Dalton’s model. B. The modern model states that atoms of all elements are identical, whereas Dalton’s model does not. C. The modern model recognizes particles in the atom, whereas Dalton’s model does not. D. The modern model does not explain emission spectra, whereas Dalton’s model does.
An emulsifying agent is typically characterized by having One polar end one nonpolar end two polar ends one polar end and one nonpolar end ------------------------------------------------------------- Also can someone please explain to me what Emulsifying means because im stuck. Thank you =D
Which statement correctly describes the relationship between reactant and yield? A. The actual yield is calculated from the amount of the excess reactant present B. The actual yield is calculated from the amount of the limiting reactant present. C. The theoretical yield is calculated from the amount of the excess reactant present. D. The theoretical yield is calculated from the amount of the limiting reactant present.
A molecular compound is formed when a chemical reaction occurs between atoms of (1) chlorine and sodium (2) chlorine and yttrium (3) oxygen and hydrogen (4) oxygen and magnesium
Which of the following is a product formed when Ag2O decomposes? Select one: a. Ag2 b. O c. O2 d. AgO