Which statement correctly explains the polarity of the water molecule? A. The hydrogen end of the molecule has a partial negative charge and the oxygen end has a partial positive charge. B. The oxygen end of the molecule has a partial negative charge and the hydrogen end has a partial positive charge. C. Both ends of the molecule have a partial negative charge, which attracts the other water molecule towards itself.
Which of the following statements describes a scientific law? a. A scientific law explains a set of events. b. A scientific law describes what occurs every time in a situation. c. A scientific law is constantly modified. d. A scientific law is developed without experimentation.
Which is the first step in the dissolving process? A.) The solute becomes like the solvent. B.) The solute molecules are carried into the solution. C.) The solvent molecules surround the solute particles. D.) The solvent molecules are attracted to particles at the surface of the solute.
The amount of heat involved in the synthesis of 1 mole of a compound from its elements with all substances in their standard states at 25 degrees celcius is called
In a nuclear reaction, mass must be lost to produce energy. Please select the best answer from the choices provided T F
H2, N2, O2 molecules. . . A)must be polar. must be nonpolar. . B)can be polar or nonpolar depending on geometric . C)configuration. . D)indeterminate
A certain ionic compound is made entirely of aluminum and oxygen. part a what is the formula for this compound?
Methanol (CH3OH) has a heat of fusion of 3.16 kJ/mol. Which of the following is the heat of solidification that occurs when 63 grams of liquid methanol freezes?
What are the weakest attractions between molecules? a. ionic forces c. covalent forces b. Van der Waals forces d. hydrogen forces
A sample of 76 g of NaCl is dissolved to make 1 L of solution. What is the molarity of the solution? Show your work.
1. Which of the following can take the shape of the container it is in but has a fixed volume?. . A. argon gas. B. liquid bromine. C. solid water. D. hydrogen plasma. 2 . In which of these samples do the molecules have the greatest kinetic energy? A. solid ice (-25 °C). B. water vapor (102°C). C. ice water (0°C). D. liquid water (54°C).
Which statement is true about radiocarbon dating? After it dies, an organism’s body continues to intake C-14. Radiocarbon dating is useful for dating objects up to 100,000 years old. Radiocarbon dating assumes that half-life for radioisotopes change over time. The half-life of C-14 is 5,730 years.
Which of the following is true about isopropyl alcohol? It is insoluble in water. It is completely odorless. It has a relatively high boiling point. It is white.
Which option describes a similarity and a difference between isotopes of an element? A) same atomic number; different number of protons B) same number of protons; different atomic number C) same atomic number; different mass number D) same mass number; different atomic number E) same number of neutrons; same number of protons
Classify each solid as a covalent, ionic, metallic, or molecular solid. Drag the appropriate items to their respective bins. HelpReset frozen ethanol calcium fluoride rhombic sulfur pure calcium
The (triangle)Hrxn of formation of carbon dioxide is negative. Which statement is true? The reaction is endothermic. The reaction is exothermic. The amount of carbon dioxide is more than the amount of reactants. The amount of carbon dioxide is less than the amount of reactants.
What does the name 2–butene tell you about this hydrocarbon's molecular structure? A.There are two carbon atoms and all single carbon bonds. B. There are two carbon atoms and a double carbon bond. C. There are three carbon atoms and a double carbon bond that starts on the second carbon atom. D. There are four carbon atoms and a double carbon bond that starts on the second carbon atom.
What causes the difference in bond angles in carbon dioxide and water? A) the distance between the atomsin either molecules B) the facr that there are tei oxygen atoms in carbon dioxide and only one in water C) the fact that the number of lone pairs of electrons on the central atom is greater in the case of water D) the presence of a carbon atom in carbon dioxide E) the presence of a hydrogen atom in water
Which of the following is not an example of a polymer? Select one: a. Polystyrene b. Nylon c. Sucrose d. PVC
Consider the following balanced reaction between hydrogen and nitrogen to form ammonia: 3H2(g) + N2(g)→2NH3(g) How many moles of NH3 can be produced from 24.0 mol of H2 and excess N2?
PLEASE HELP I WILL GIVE YOU 50 POINTS Which of the following aqueous solutions will have the lowest vapor pressure at 25°C? 1.5 M C6H12O6 1.5 M LiNO3 1.0 M Al2O3 1.0 M CaF2
Which radioisotope is used as a tracer in nuclear scanning? carbon -14 uranium-238 technetium-99m iodine-129
Which is most likely why many scientists reject the cold fusion theory? There is too much waste involved in the process. Cold fusion experiments have been conducted at room temperature only. The process does not produce enough energy to meet the needs of modern humans. The original results have not been replicated consistently and reliably.
Which statement defines calorimeter? a device that measures the heat that is gained or lost in a chemical change a device that measures the potential energy of an element a device that is used to measure heat capacity a device that is used to measure temperature
What is the net ionic equation of the reaction of BeCl2 with NaOH? Express your answer as a chemical equation. I have an answer, but everytime I enter it it says invalid format.. :/