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How do you measure your diagrams with no calculation in magnitude+ direction?

What is the difference between gravity filtration and vacuum
filtration?
When should vacuum filtration be used?
What is the difference between copper (II) sulphate trihydrate, copper (II) sulphate pentahydrate, and anhydrous copper (II) sulphate?

Methane, CH4 , the major component of natural gas burns in air to form CO2 and H2O. What mass of water is formed in the complete combustion of 5.00 x 103 g of CH4?
Why is the answer: 11.2 kg.
Thank you.

When the following equation is balanced in standard form, what is the coefficient in front of CO2(g)?
C2H6(g) + O2(g) ® CO2(g) + H2O(l)
A)1
B)2
C)3
D)4
E)5

A pure organic substance (1.000 g) containing C, H, and O, undergoes combustion analysis. The mass of the water obtained is 0.6662 g. What is the mass percent of hydrogen in the compound?
a. 3.699%
b. 7.456%

Which one of the following cannot be an empirical formula?
c) C2H4O
d) C2H4O2

What is computing derivative definition and how do you use #f(x+h)f(x)/h#?

What is rational function and how do you find domain, vertical and horizontal asymptotes. Also what is "holes" with all limits and continuity and discontinuity?

For the following function:
g(x) = 2x + 2 / x^2  6x  7
(a) Find the domain.
Answer ..................
(b) horizontal asymptotes ?
(c) vertical asymptotes ?
(d) is there discontinuity?

For the following function:
g(x) = x^2 + 4x  5 / x^2 + 7x + 10
(a) Find the domain.
Answer ..................
(b) horizontal asymptotes?
(c) vertical asymptotes ?
(d) is there discontinuity ?

What would be the cost in dollars of nails for a fence 88 feet long if one needs 9 nails per foot of fence, there are 36 nails in a pound, and they sell for 69 cents per pound?

A mass of 182 g of benzene, an important organic solvent, fills a measuring cylinder to the 207 mL mark. How to calculate the density of benzene: (a) in #"g/ cm"^3#? (b) in #"kg/m"^3#?

An oxide of aluminium is formed by the reaction of 4.151g Al with 3.692 g O. How to calculate its empirical formula ?

A) How to calculate the theoretical yield of water resulting from the complete combustion of 1.60 g of methane
b) When the reaction was run in the lab 3.30 g of water were formed. What is the percent yield of water for this run?
CH4 + 2 O2 >CO2 + 2 H2O?

The specific heat capacity of platinum is 0.032 cal/g·K. How to calculate the heat, in joules, necessary to raise the temperature of a sample of platinum weighing 20.0 g from 15.0 Celsius to 65.0 Celsius?

When 9.41 g of phenol, C6H5OH, are burned in a bomb calorimeter at 25 oC, 305.1 kJ of heat are given off. How to calculate the standard enthalpy of combustion, in kJ/mol, of phenol?

How many moles of ammonia are there in a 5.00 L cylinder if they exert a pressure of 8.65 atm at 18.0 Celsius?

At 18.0 Celsius and 765 torr, 2.29 dm^3 of a gas weigh 3.71 g. How to calculate the approximate molar mass, in g/mol, of the gas?

A certain gas has a density of 1.30 g/L at STP. What will its density, in g/L, be at 546 K and 380 torr pressure ?

How to calculate the root mean square speed, vrms, in m·s^1 at 227 Celsius and 900 torr, of a gas having a molar mass of 16.0 g·mol^1 ?

A certain saturated hydrocarbon effuses about half as fast as methane, #CH_4#. What is the molar mass, in g/mol, of this hydrocarbon ?

How many grammes of zinc metal are required to produce 10.0 litres of hydrogen gas, at 25 Celsius and 1.00 atm pressure, by reaction with excess hydrochloric acid?
Zn (s) + 2HCl (aq) ZnCl2 (aq) + H2 (g) ?

The valve connecting a 2.00 L bulb containing N2 at 530 torr and a 3.00 L bulb containing O2 at 195 torr is opened. After equilibration what is the total pressure, in atm, in the system?

The ionisation energy of gold is 890.1 kJ/mol. Is light with a wavelength of 225 nm capable of ionising a gold atom ?

What is the wavelength, in nm, of a photon emitted during a transition from the n = 5 state to the n = 2 state in the hydrogen atom ?

How to calculate the de Broglie wavelength, in nm, of a baseball with m = 200 g and u = 30 m/s ?

What is the maximum number of electrons that can be present in the shell specified by n = 3?

When a cook heats water to make pasta, energy flows _____ the pot of water, so DH is _____.
A) into, 0
or
B) into, > 0 ?

When dew forms on grass overnight, which of the following statements is true?
A) The process is accompanied by an increase in temperature
B) The process is accompanied by a drop in temperature ?

The amount of energy needed to heat 2.00 g of carbon from 50.0°C to 80.0°C is 42.6 J. The specific heat capacity of this sample of carbon is ?

Which one of the following represents an element in its standard state at 25°C and 1 atm?
A) Fe(l)
B)Br2 (l)

How to find extrapolated temperature?

What is the standard change in enthalpy of formation of #"MgO"(s)#?

Differentiate the function. Y= √x(x8) ?

How to find f '(a).
f(x) = √ 26x ?

The rootmeansquare speed of a gas is found to be 391.2 m/s at 270 K. The gas is ?

An 11.2 litre cylinder contains oxygen gas at STP. Assuming that oxygen behaves ideally at STP, how many molecules are there in the cylinder ?

True about kinetic molecular theory?
a) The volume of the gas particles is negligible compared to the average distance between any two particles.
b) Pressure is due to the collisions of the gas particles with the walls of the container?

Which substance in the reaction below either appears or disappears the fastest? 4NH3 +7O2 > 4NO2 +6H2O
a) NH3
b)O2
c)NO2
d)H20

Octane (C8H18, 114.23 g/mol). The density of octane vapour 125.0 Celsius and 720.0 torr is ? and what would be the volume be if it was 2.00 moles ?

How do you calculate enthalpy change?

You have 250.0 mL of 4.00 M sugar solution. You add 300.0 mL of water to this solution. What is the concentration of the sugar solution after the water has been added?
a) 3.33 M
b) 1.82 M
c)1.54 M
d) 2.00 M
e) 2.18 M

You prepare 3.00 L of 0.250 M HNO3 from a stock of nitric acid that is 12.0 M. What volume of the stock solution will you require to make the dilute solution?
a) 0.0625 mL
b) 62.5 L
c) 144 L
d) 62.5 mL

Consider a steel container filled with 40.0 g of helium gas and 40.0 g of argon gas. What is the ratio of pressures that each gas exerts (helium:argon)?
a) 1:1
b) 10:1
c) 1:10
d) 9:1

You have a sample of neon gas at a certain pressure, volume, and temperature. You double the volume, double the number of moles of neon, and double the Kelvin temperature. How does the final pressure (Pf) compare to the original pressure (Po) ?

Find an equation of the tangent line to the curve at the given point ?
y= (sqrt x) , (49,7)

The wavelength of the green light from a traffic signal is centred at 522 nm. What is the frequency, v, in Hz, of this radiation?

How to calculate the energy, in joules, of a photon of wavelength 5.00*10^4 nm ?

How to find the derivative function of #g(x) = 3/(x2)#?
f(x)= f(x+h)f(x) / h

An oxygen atom has a total of 8 elections. How do you write the 4 quantum numbers for each of the 8 electrons in the ground state ?

How to find derivatives with simplified form for this equation?
#(x^21)/(x^2+1)#

How to write the electron configuration for sulfur? (z=16)

For the following function: g(x) = (3x+9) / (x^2x12) (a) Find the domain. Answer .................. (b) horizontal asymptotes? (c) vertical asymptotes ? (d) is there discontinuity ?

The maximum energy that a hydrogen atom can have is 0 J, at which point the electron is essentially removed from the atom; thus ionization occurs. How much energy ( in joules ) does it take to ionize a hydrogen atom? What wavelength to ionize a hydrogen?

What is the molar mass of a compound if 5.19*10^16 molecules of the compound weigh 6.205 microgrammes?

A certain sold has a density of 8.0 #"g/cm"^3#. If 16.0 g of this solid are put into 4.00 mL of water, which drawing below most closely represents the volume of water after the solid is added?

The mass of a proton is #1.67*10^(27)# kg. What is the mass of a proton in picograms?

By analogy with the oxoanions of sulfur, H2TeO3 would be named?

The element antimony has an atomic weight of 121.757 u and only two naturally occurring isotopes. One isotope has an abundance of 57.3% and an isotopic mass of 120.904 u. What is the mass of the other isotope?

10.0g of a metal, initially at 25 Celsius, are placed into 10.0 g of water, initially at 100 Celsius. Which metal will have the lowest final temperature?
A) Aluminium (0.902 J/g*Celsius)
B) Gold (0.129 J/g* Celsius)
C) Copper (0.385 J/g*Cesius)

Given : S(s) + O2(g) > SO2 (g) Delta H= 296.1 kJ
2SO3(g) > 2SO2(g) + O2(g) Delta H= 198.2 kJ
How to find the Delta H for :2S(s)+3O2(g) > 2SO3(g)?

At constant pressure, the combustion of 5.00 g of C2H6 (g) releases 259 kJ of heat. What is ΔH for the reaction?
2 C2H6(g) + 7 O2(g) → 4 CO2(g) + 6 H2O(l)

Acetylene torches utilize the following reaction:
2 C2H2 (g) + 5 O2 (g) > 4 CO2 (g) + 2 H20 (g)
How to calculate Delta H in Celsius for this reaction ?
Species Delta H
C2H2 (g )= +226.7
CO2 (g )= 393.5
H20 (g) = 241.6

In the combustion analysis of an unknown compound containing only carbon , hydrogen and oxygen, the grams of oxygen are found from the grams of?
A) CO2 and unknown compound
B) CO2,H2O and unknown compound

All the atoms of a particle element have an equal number of protons and neutrons (Z=N). Which one is true?
A) The atomic weight must be a whole number.
B) The mass number must be exactly twice the atomic number for each atom.

A packet of energy is called ?
a) a wavelength
b) a wave
c) a quantum
d) a proton

Which of the transitions in the hydrogen atom energylevel is the longest wavelength photon?

When an electron in the ground state absorbs energy, it goes to a/an ______________ state ?

The energy of a oneelectron atom or ion is given by Bohr’s equation. Which one of the following oneelectron species has the lowest energy ground state?
a)Li2+
b) He+
c)Be3+
d) B4+
e) H

Indicate which of the following photons can cause emission of photoelectrons from the surface of gallium ( 6.7 × 10–19 J)?
A) 300 nm
B) 400 nm
C)

The form of electromagnetic radiation that has more energy per photon than ultraviolet rays but less energy per photon than gamma rays is ?
a) microwaves
b) radio waves
c) Xrays

What is the frequency of the photons emitted by a HeNe laser with a wavelength of 632.8 nm?

Which orbitals has the electron with the greatest penetrating ability?

The maximum number of electrons allowed in an individual d orbital is?

Which one of the following is the groundstate electron configuration of the Mg2+ ion?

The probability envelope for an electron is called?

Which one of the following sets of quantum numbers (l and ml) corresponds to the orbital with the highest energy in the n = 3 shell?

Which of the following is an incorrect designation for an atomic orbital?
a) 1s
b) 4f
c) 3s
d) 2d
e) 2p

A baseball with a mass of 150 g is moving at a velocity of 40 m/s (90 mph). If the uncertainty in the velocity is 0.1 m/s, the minimum uncertainty in position is ?

What is the speed of an argon atom that has a de Broglie wavelength of 5.2 pm?

How to calculate the first and second ionization energies of helium?

How to calculate the effective nuclear charge of the 1s electrons in helium ?

How to compare the formal charge and oxidation number of the chlorine atom in the chlorate ion ?
#
#

How to estimate (Delta H) for the bromination of ethylene from bond dissociation energies ?

What is the steric number of the central atom in the following species ?
a) Carbon dioxide, CO2
b) Ammonia, NH3
c) Ammonium ion
d) Formaldehyde

What does it mean by the frequency of electromagnetic radiation?
Is the frequency the same as the speed of the electromagnetic
radiation?

An FM radio station broadcasts at 99.5 MHz. How to Calculate the
wavelength of the corresponding radio waves ?

Microwave radiation has a wavelength on the order of 1.0 cm.
Calculate the frequency and the energy of a single photon of
this radiation. How to calculate the energy of an Avogadro’s number
of photons (called an einstein) of this radiation ?

Which one of the following ions is isoelectronic with krypton? (a) #Ca^(2+)#, (b) #K^+# (c) #I^# (d) #Mg^(2+)# (e) #Sr^(2+)#

Which one of the following substances would you expect to have the largest lattice energy (absolute value)?
a) CsI
b) RbCl
c) NaBr
d) NaI
e) NaF

Which arrangement is in the correct order of radius size?
a) Mn > Mn2+ > Cs
b) Li+ > Li > Ra
c) P < P3– < As3–
d) Cr < Cr3+ < Ca
e) Al3+ > Al > Si

Which one of the following bonds would you expect to be the most polar?
a) B–H
b) N–H
c) P–H
d) Al–H
e) C–H

Which group of elements is listed in order of increasing electronegativity?
a) F, Cl, Ge, Sn
b) Rb, Ca, Sc, Cs
c) Zr, V, Nb, Ta
d) Sn, As, P, S
e) Li, Na, K, F

The work function of an element is the energy required to remove
an electron from the surface of the solid element. The
work function for lithium is 279.7 kJ/mol. What is the maximum
wavelength of light that can remove an electron from an
atom ?

How to Calculate the de Broglie wavelength for each of the following ?
a. an electron with a velocity 10.% of the speed of light
b. a tennis ball (55 g) served at 35 m/s (,80 mi/h)

lim x>1 f(x) = ?

What is the lattice energy?

Which of the following compounds exhibits only dispersion and dipoledipole intermolecular
interactions ?
A) HBr B) CO2 C) H2O D) N2

Arrange the following spectral regions in order of increasing wavelength ?
A) microwave < infrared < visible < ultraviolet
B) ultraviolet < infrared < visible < microwave
C) ultraviolet < visible < infrared < microwave

What is the oxidation number of the sulfur atom in Li2SO4 ?
A) +4 B) +6 C) +2 D) 2

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