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# General Chemistry

### MO theory and dissociation energy

Use simple MO Theory (LCAO-MO) to explain why the dissociation energy of neutral N2 is greater than the N2+ ion, but that the dissociation energy of the O2+ ion is greater than the O2 neutral.

### Body Temperature From Fahrenheit to Celsius and Kelvin

Express normal body temperature, 98.6 degF, in degC and K.

### Degrees of freedom of a saturated solution

A saturated solution of Na2SO4 with excess of the solid is present in equilibrium with its vapor in a closed vessel. Calculate the number of degrees of freedom, f, of the system. Ignore the autoprotolysis of water and assume that the salt solvates without ionizing. F = c - p +2 or use f = c-p +2 -r -a c = chem species

### Balancing molecular,ionic,and net ionic equations

Lead II nitrate + lithium chloride = lead II chloride + lithium nitrate

### Calculate the Number of Moles

A steel tank with a volume of 9.583 L contains N2 gas under a pressure of 4.972 atm at 31.8 °C. Calculate the number of moles of N2 in the tank.

### Finding balancing coefficients of chemical reactions

What is the coefficient of O2? _Al+_O2-> Al2O3

### Balancing chemical reactions

When the following equation is balanced, the coefficients of BaO2 is? _BaO2-> BaO+ _O2

### Hydrogen Gas and the Ideal Gas Law

I need some help finding the volume of the hydrogen generated if the temperature at the depth of the Titanic is -1 degrees Celsius.

### AP Chemistry: Test Review

(See attached file for full problem description) --- I need full explanation of each step. Please help. 1. The helium ion, He+, has energy levels similar to those of the hydrogen atom, since both species have only one electron. The energy levels of the He+ ion are given by the equation En = - 5248.16 kj/mole n =

### Percentage yields

A chemist isolates 17.43 g of product from a reaction that has a calculated theoretical yield of 21.34 g. What is the percentage yield?

### Volume required to prepare molar solution

What volume of 0.125 M KOH is required to prepare 750 ml of 0.06500 M KOH?

### Solubility of Rb2S, Li2Cr2O7, Cu(ClO4)2

Is Rb2S, Li2Cr2O7, Cu(ClO4)2 insoluble or soluble and why?

### Solubility of KOH in Water

KOH Is this soluble or insoluble in water? What rules of solubility makes this so?

### Molarity calculation for NH3 solution

What volume (L) of 0.750 M NH3 solution would you use to prepare 0.500L of 0.250M NH3 solution?

### Wavelength and Frequency Example Problem

Question 1: M. tuberculosis, the organism that causes tuberculosis, can be completely destroyed by irradiation with UV light with a wavelength of 254 nm. What is the frequency? Question 2: Aradio station's signal broadcasts at a freq. 1240kHZ. What is the wavelength in meters?

### Oxygenate Octane Enhancers

A) What is an oxygenate? b) Name one octane enhancer

### Chemical Symbol Elements

Give the name and chemical symbol for: a) An element with 50 electrons b) An element with 28 protons c) An element with 2 electrons in the first shell, 8 electrons in the second shell, 8 electrons in the third shell, and 2 electrons in the fourth shell d) An element with atomic number of 78

### Distinguish Ionic or Covalent Bonding

While you are working in the lab your instructor hands you a vial of red, crystalline material and asks you to tell if it has ionic or covalent bonding. Describe at least one experiment you would do to answer the instructor's question.

### Compound or a mixture?

Tell whether the following is a property of a compound or a mixture: a) Can contain three elements in a specific ratio b) Varies in chemical composition depending on the sample size c) Can be classified as either homogeneous or heterogeneous

### Heterogeneous and homogeneous mixture

Tell if the mixture is homogeneous or heterogeneous and explain why you classified it as homogeneous or heterogeneous. a) Iced tea b) Salad c) Chocolate chip cookie

### Principal environmental concerns about the continued use of plastics

What is the principal environmental concerns about the continued use of plastics? Name some secondary concerns.

### Volatility

Suppose you were given samples of two different liquids. Describe how you would determine which one is more voliatile.

### Converting Gas Mileage from Metric to English

If auto gas mileage of 28.5 miles per gallon, how many kilometers can it travel on 1.0 litre of gas? What is formula to figure?

### Working with molecules in first excited rotational state

Calculate the ratio of HCL molecules in the first excited rotational state to those in the ground state @ 25 C. Assume an equilibrium bond distance of 1.275 angstroms. the angstrom part of the problem throws me off, I usually start these out by solving Change in E = ( h ) ( c )(Wo), but this is a q (rot) prob, not a q (elec).

### Chemical Symbol of First 10 Atomic Numbers

What chemical symbol is used as the equivalent of 2superscript 1subscript H? Name and give the chemical symbols for the elements with the first 10 atomic numbers.

### Isotopes of Hydrogen Elements

Name the three isotopes of the element whose atomic number is 1. (b) What collective name do we give to a mixture of these three isotopes when they are present in the same ratios as in the universe as a whole?

### Dipole-dipole forces

Which molecule does not exhibit dipole-dipole forces. SO2, ICl, H2O, CH4.

### Conversions

The volume of a certain bacterial cell is 1.60 µm3. (a) What is its volume in cubic millimeters (mm3)? (b) What is the volume of 105 cells in liters (L)? [show all the conversion factors that were used in calculating the answers]

### Particle in a Box Proportionality

A particle is constrained to lie along a one-dimensional line segment between 0 and a. The probability of finding the particle along this line segment is seen in attached file. A. Find the proportionality constant, ie., normalize the function. B. Calculate the expectation values of X and X^2 for n=1 and n=2. C. Find t

### Mathematic Notation Problem

Explain. 4.4 x10 -2 ) (2.2 x 10-7) that is 10 to the minus 2 and 10 to the minus 7.