Which of the following is a radioisotope used to date rock formations older than 50,000 years old? A) carbon-12 B) uranium-235 C) cobalt-60 D) carbon-14 Any help is appreciated :)
Calculate the approximate enthalpy change, ΔHrxn, for the combustion of methane: CH4+2O2→2H2O+CO2 ΔHrxn from a given table: CH4 = 1656 kJ/mol O2 = 498 kJ/mol H2O = 928 kJ/mol CO2 = 1598 kJ/mol ΔHrxn = [(1656) + (2*498)] - [(2*928) + (1598)] = -802 kJ/mol ?
A single atom of an element has 11 protons, 11 electrons, and 12 neutrons. Which element is it? A. V B. Na C. Mg D. Se
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
An unknown sample required 21.05 mL of 0.02047 M KmnO4 to reach the end point. How many moles of KmnO4 reacted?
Hikers have noticed that a sealed bag of potato chips puffs up when taken to the top of a mountain. Suppose that at the valley floor below, the air pressure is 1.0 atm, temperature is 25°C, and the volume of the chip bag is 0.985 L. At the top of the mountain, the temperature is 22°C and the chip bag has puffed up to 1.030 L. What is the air pressure on top of the mountain?
The transfer of heat by the movement of heated fluid is called conduction. Please select the best answer from the choices provided T F
In part B of my question, I was asked calculate the number of atoms in 0.615 mol of 13C (mass number of this Carbon is 13). I received the correct answer of 3.70E23 atoms. However, I do not know how to do Part C of my question, which asks "Based on your answer in Part B, how many electrons are in this amount of 13C"? Similarly, Part D asks "how many neutrons are in this amount of 13C"? Thank you so much in advance!
Determine the overall charge on each complex.a) tetrachlorocuprate(i)b) pentaamminechlorocobalt(iii)c) diaquadichloroethylenediaminecobalt(iii)
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
Which best characterizes a crystal? a number of high speed particles moving randomly a dense substance that is hard and incompressible a high-energy state of matter made up of a swirling, ionized gas a loose association of particles moving past one another
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.
____ is the transfer of energy in the form of rays or waves. a. Conduction c. Radiation b. Convection d. Condensation
How much nitrogen-14 will be produced from a 200-g sample of carbon-14 after 17,190 years? Download png
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.
Which of the following is an example of a nonmetallic mineral? a. sulfur b. lead c. aluminum d. gold
Which type of condensation nuclei are most likely to cause clouds to form? a. smoke particles b. dust particles c. salt particles?
Assuming equal concentrations and complete dissociation, rank these aqueous solutions by their freezing points. NH4l, CoBr3, Na2SO4
What is always true of a combustion reaction? carbon dioxide will be produced the reaction absorbs energy oxygen gas must be one of the reactants one reactant must contain carbon
Calculate the molar solubility of fe(oh)2 in pure water. (the value of ksp for fe(oh)2 is 4.87×10−17.)