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What is the result of the following equation with the correct number of significant figures? (400-84125)/(0.0110+4.818910^4)+6.52810^-3
What is the result of the following equation with the correct number of significant figures? (400-84125)/(0.0110+4.818910^4)+6.52810^-3
-1.73
What is the result of the following equation with the correct number of significant figures? (42.8841*3.29)+332.58
What is the result of the following equation with the correct number of significant figures? (42.8841*3.29)+332.58
473
Explain the differences between a scientific law and a scientific theory.
Explain the differences between a scientific law and a scientific theory.
A law is a pattern produced by data. A theory uses laws to base a testable hypothesis and it's never entirely true.
At liftoff, an orbiter and External Tank carry 3.1644 x 10^6 L of fuel. The density of the fuel was 1.14 g/cm³, what is the mass of the fuel in mg?
At liftoff, an orbiter and External Tank carry 3.1644 x 10^6 L of fuel. The density of the fuel was 1.14 g/cm³, what is the mass of the fuel in mg?
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From the description below, identify the physical and chemical properties of sodium hypochlorite, NaClO. Sodium hypochlorite (NaClO) is unstable and can decompose explosively to chlorine gas. NaClO is a solid at room temperature and has a density of 1.11 g/cm³.
From the description below, identify the physical and chemical properties of sodium hypochlorite, NaClO. Sodium hypochlorite (NaClO) is unstable and can decompose explosively to chlorine gas. NaClO is a solid at room temperature and has a density of 1.11 g/cm³.
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What is precision?
What is precision?
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What is accuracy?
What is accuracy?
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What are isotopes?
What are isotopes?
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Determine each of the following for an atom of tellurium-127: A) Mass number B) Atomic number C) Number of protons D) Number of neutrons E) Number of electrons
Determine each of the following for an atom of tellurium-127: A) Mass number B) Atomic number C) Number of protons D) Number of neutrons E) Number of electrons
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Name each compound: A) Na3PO4 B) P4O10 C) Cu(NO3)
Name each compound: A) Na3PO4 B) P4O10 C) Cu(NO3)
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Write the formula for the compound or ions: A) Copper(II) nitride B) Dinitrogen tetroxide C) Iron(III) sulfate
Write the formula for the compound or ions: A) Copper(II) nitride B) Dinitrogen tetroxide C) Iron(III) sulfate
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The distance between two atoms in a molecule is 5.470*10^-9 inches. What is the distance in units of picometers?
The distance between two atoms in a molecule is 5.470*10^-9 inches. What is the distance in units of picometers?
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Arrange the atoms and ions in order of increasing number of electrons: 40^K, 50^V^+, 53^Mn^4+
Arrange the atoms and ions in order of increasing number of electrons: 40^K, 50^V^+, 53^Mn^4+
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In a lab, you are given an aqueous solution of an unknown salt that contains Pb^2+ and Ba^2+. Which of the following aqueous salts could be added to precipitate out the Pb^2+ ions but not the barium ions?
In a lab, you are given an aqueous solution of an unknown salt that contains Pb^2+ and Ba^2+. Which of the following aqueous salts could be added to precipitate out the Pb^2+ ions but not the barium ions?
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What is the net ionic equation for the following reaction? K3PO4(aq) + CaCl2(aq) -->
What is the net ionic equation for the following reaction? K3PO4(aq) + CaCl2(aq) -->
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What is the concentration of a 50.0 ml sample of H2SO4(aq) if 23.74 ml of 0.400 M NaOH(aq) was required to completely react with the H2SO4(aq)?
What is the concentration of a 50.0 ml sample of H2SO4(aq) if 23.74 ml of 0.400 M NaOH(aq) was required to completely react with the H2SO4(aq)?
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Consider the following reaction: 2NO(g) + 5H2(g) --> 2NH3(g) + 2H2O(g). A reaction mixture initially contains 5 moles of NO and 10 moles of H2. How much (in moles) is present of each substance after the reaction goes to completion?
Consider the following reaction: 2NO(g) + 5H2(g) --> 2NH3(g) + 2H2O(g). A reaction mixture initially contains 5 moles of NO and 10 moles of H2. How much (in moles) is present of each substance after the reaction goes to completion?
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Combustion analysis of a hydrocarbon that only contains hydrogen and carbon produces 13.2 g CO2 and 1.80 g H2O. What is the empirical formula of the hydrocarbon?
Combustion analysis of a hydrocarbon that only contains hydrogen and carbon produces 13.2 g CO2 and 1.80 g H2O. What is the empirical formula of the hydrocarbon?
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Study Notes
Significant Figures in Calculations
- Example equation: ((400-84125)/(0.0110+4.8189 \times 10^4)+6.528 \times 10^{-3}) results in (-1.73).
- Example equation: ((42.8841 \times 3.29)+332.58) results in (473).
Scientific Law vs. Theory
- A scientific law describes a consistent, observable pattern in data.
- A scientific theory explains phenomena using laws and can be tested but is subject to revision.
Fuel Mass Calculation
- Given: (3.1644 \times 10^6 , L) of fuel with a density of (1.14 , g/cm^3).
- Calculated mass of fuel: (3.61 \times 10^9 , mg).
Sodium Hypochlorite Properties
- Physical properties: solid at room temperature, density of (1.11 , g/cm^3).
- Chemical properties: unstable, can decompose explosively to chlorine gas.
Definitions of Precision and Accuracy
- Precision: consistency of repeated measurements.
- Accuracy: closeness of a measurement to its true value.
Isotopes
- Isotopes are variants of the same element that differ in the number of neutrons.
Tellurium-127 Characteristics
- Mass number: (127).
- Atomic number: (52).
- Number of protons: (52).
- Number of neutrons: (75).
- Number of electrons: (52).
Naming Compounds
- (Na_3PO_4): sodium phosphate.
- (P_4O_{10}): tetraphosphorus decoxide.
- (Cu(NO_3)): copper nitrate.
Writing Chemical Formulas
- Copper(II) nitride: (Cu_2N).
- Dinitrogen tetroxide: (N_2O_4).
- Iron(III) sulfate: (Fe_2(SO_4)_3).
Atomic Distance Conversion
- Distance between atoms: (5.470 \times 10^{-9} , inches) is equivalent to (138.9 , pm).
Electron Count of Atoms and Ions
- Atoms/Ions in increasing order of electrons: (K^+, , V^{2+}, , Mn^{4+}).
Precipitation Reactions
- To precipitate lead ions ((Pb^{2+})) without affecting barium ions ((Ba^{2+})), add (KCl).
Net Ionic Equations
- Net ionic equation for the reaction (K_3PO_4(aq) + CaCl_2(aq)): (3Ca^{2+}(aq) + 2PO_4^{3-}(aq) \rightarrow Ca_3(PO_4)_2(s)).
Concentration of H₂SO₄
- Concentration calculation based on reaction with (NaOH): (0.0950 , M).
Reaction Completion Calculation
- For the reaction (2NO(g) + 5H_2(g) \rightarrow 2NH_3(g) + 2H_2O(g)) with initial moles:
- Final amounts: (1 , mol , NO), (0 , mol , H_2), (4 , mol , NH_3), (4 , mol , H_2O).
Empirical Formula Determination
- Combustion of a hydrocarbon producing (13.2g , CO_2) and (1.80g , H_2O) results in the empirical formula (C_3H_2).
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Description
This quiz features important mathematical calculations and scientific concepts, including the application of significant figures and the differences between scientific laws and theories. Test your understanding of these crucial topics as you prepare for your midterm exam.
