Explain the law of conservation of mass and the law of

Question

COURSE: GENERAL CHEMISTRY

QUIZ #1:

Part 1

QUESTION #1:

Mention three states of the matter, and describe them according to their volume shape, and if are flexible/rigid/compressible

QUESTION #2(:

The matter can be classified between "pure substances" (elements and compounds) and "mixtures" (homogeneous and heterogeneous). In what kind of matter can be used the distillation as a technique to separate desired liquids?

QUESTION #3:

Write the names and symbols of the units from the International System (SI) of the following parameters:

Temperature, mass, volume, time, amount of substance, length

QUESTION #4:

Explain the Law of Conservation of Mass and the Law of Conservation of Energy.

QUESTION #5:

Convert 1,235,742.66 L into km³ using 4 significant figures. Use rounding rules and write it in scientific notation.

QUESTION #6:

Give the definition of Atomic Number (Z), atomic mass (A), and isotope

QUESTION #7:

How many moles contain 100 g of Ni ?(Nickel, use the Periodic Table to know the mass number) How many atoms does it have? (Use 3 significative figures and apply rounding rules if needed)

QUESTION #8:

Explain the difference between ionic bonds and covalent bonds

QUESTION #9:

From the following options, identify which of them are ionic compounds and which are molecular compounds (just put "ionic" or "molecular"). Name each of them

HCl_(aq)=

NaCl=    

N₂O=    

KCl=

CaO=

CO₂=

QUESTION #10:

Describe characteristic properties of acids about taste and with the interactions with metals.

Part 2

QUESTION #1:

Determine above each element the corresponding oxidation number. Don't confuse it with electrical charge of ionic compounds.

Hg                    K⁺                     CCl₄                       NO₃^-                 OH^-

QUESTION #2:

For the next chemical equations:

C_(s) + O_2(g)                     CO₂

2Li_(s) + Cl_2(g)                   2LiCl_(s)

CaO_(s) + CO_2(g)               CaCO_3(s)

Show  if there is redox reaction, if so show which element is the oxidizing agent and which is the reducing agent. Assign the oxidation numbers to each element in the equation.

QUESTION #3:

A gas sample at STP conditions contains 1.15g of oxygen  and 1.55g of nitrogen. What is the volume of the gas sample?

QUESTION #4:

Rank the following gases: Ar, N₂, CH₄, Cl₂ and C₂H₆ in order of increasing density based on the molar masses (show the values of the molar masses).

QUESTION #5:

Balance the chemical reaction of the combustion of ethane with oxygen to produce carbon dioxide and water

C₂H_6(g)  +         O_2(g)                                   CO_2(g)   +          H₂O_(g)

_{part 3}

QUESTION #1:

Define specific heat capacity of a material (C_s) and explain the implications of this concept in a comparison between a material with a very small C_s and water that has a very high value of C_s

QUESTION #2:

A 0.1500 kg granite block initially at 20.50°C absorbs 205.0 cal of heat. What is the final temperature of granite in Kelvins? (give the result with 4 significative figures) (the data about conversion units and C_s of granite are in lesson#9)

QUESTION #3:

A balloon at 380 mm Hg lost a volume of 650 ml. Calculate the work of this volume change. Give the value in Joules with the right sign (+ or -)

QUESTION #4:

The change in energy can be expressed through the following formula:

?E = q + w

Where q is heat and w is work. In a calorimeter, which of those two kinds is NOT studied and why?

QUESTION #5:

Calculate the frequency of a part of the visible light spectrum that has a wavelength of 0.405 μm

QUESTION #6:

Order the components from the electromagnetic spectrum in increasing energy level (show the calculations of each value of energy):

1) Microwaves with wavelength  of 10^-2 m

2) X rays with wavelength of 10^-10 m

3) Radio waves with wavelength of 500 m.