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Matriarchy refers to:
1. 5 answers
2. 92 views
The main purpose of higher education is for students to be able to get a jobTrue False
1. 29 answers
2. 131 views
conditions for continuity
1. 1 answer
2. 90 views
prove that between two rational number there is an irrational
1. 1 answer
2. 97 views
Suppose that |x-2|<0.01 and |y-3|<0.04 .Use the Triangle Inequality to showthat |(x+y)-5|<0.05 represent your solution on a
1. 1 answer
2. 104 views
State without proof the Binomial Series.
1. 1 answer
2. 131 views
prove the binomial theorem
1. 1 answer
2. 124 views
Find the term independent of x in the expansion of (x^4-2/3x)^100
1. 1 answer
2. 229 views
Find the term independent of x in the expansion of100 4 3 2      x x
1. 1 answer
2. 128 views
prove the binomial theorem?
1. 1 answer
2. 104 views
evaluate lim x=0 (sin 3x cot 5x)/(xcot 4x)
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2. 84 views
evaluate lim x=0 [(sin 3x cot 5x)/(xcot 4x)]
1. 1 answer
2. 95 views
evaluate lim x=0 (Evaluate sin 3x cot 5x/xcot 4x)
1. 1 answer
2. 115 views
Evaluate     x x x x x cot 4 sin 3 cot 5 lim
1. 1 answer
2. 114 views
Prove by Principle of Mathematical Induction that for every positive integersn , 3^n >n^2
1. 3 answers
2. 178 views
Determine the empirical formula of an unknown Compound having a percent composition of 3.74% H, 17.83% C, and 38.43 % Pb.(Molar
1. 1 answer
2. 149 views
Calculate the internal energy for the reaction shown below which was performed at constant pressure of 40 Pa and a volume of 1.0
1. 1 answer
2. 110 views
An object weighs 34 Kg on earth. Note: The Earth's gravitational field strength is 10 N/kg. How would you describe the object?It
1. 1 answer
2. 123 views
An object weighs 34 Kg on earth. Note: The Earth's gravitational field strength is 10 N/kg. How would you describe the object?
1. 1 answer
2. 140 views
Using Hess law, calculate ΔH for the equation: O3 (g) +2NO2 (g)→ N2O5 (g) + O2 (g)Given the following equations: N2O5 (g)
1. 1 answer
2. 179 views
A limiting reagent in a chemical reaction:Is used up at the end of the reaction and affects the yield of the reaction
1. 1 answer
2. 195 views
Find the root mean square velocity of molecules of gaseous phosphoric acid H3PO4 at 158°C. (Molar mass: O= 16 g/mol, H 1 g/mol,
1. 1 answer
2. 126 views
Propene, C3H6 (100 g) was subjected to combustion. The actual yield of carbon dioxide is 200 g. Calculate the percent yield of
1. 1 answer
2. 214 views
Propene, C3H6 (100 g) was subjected to combustion. The actual yield of carbon dioxide is 200 g. Calculate the percent yield of
1. 1 answer
2. 169 views
Four students measured the density of sea water which is shown in the table below. Which of the student results are more
1. 1 answer
2. 115 views
0.25 g of sodium hydroxide reacts with hydrogen bromide to form sodium bromide. How many grams of sodium bromide can be
1. 1 answer
2. 179 views
A container of gas with a volume of 952 mL at a temperature of 321 K exerted a pressure of 108 atm. Calculate the pressure of
1. 1 answer
2. 159 views
A container of gas with a volume of 952 mL at a temperature of 321 K exerted a pressure of 108 atm. Calculate the pressure of
1. 1 answer
2. 123 views
An unknown compound was subjected to combustion.6.608 g of water together with 12.923 g of carbon dioxide and 2.501 g NH3 were
1. 1 answer
2. 145 views
Using the table below that shows some values for standard enthalpy changes of combustion, calculate the standard enthalpy change
1. 1 answer
2. 161 views
Using the table below that shows some values for standard enthalpy changes of combustion, calculate the standard enthalpy change
1. 1 answer
2. 159 views
A chemical reaction releases 2.34 kJ of heat and no work is done on the surroundings. What happens to the change in internal
1. 3 answers
2. 109 views
12.915 g of a compound was combusted in excess oxygen in which 7.749 g of H2O and 18.942 g of CO2 were produced. Determine the
1. 1 answer
2. 149 views
Which one of the following is not an extensive property?enthalpy mass work volume
1. 1 answer
2. 110 views
Which one of the following is not an extensive property?
1. 1 answer
2. 98 views
Peter conducted an experiment to investigate how much water a paper towel could absorb. Initially, He found that one paper towel
1. 1 answer
2. 157 views
Using Hess law, calculate ΔH for the equation: N2O3 ---> NO + NO2N2O3 ---> N2 + 3⁄2O2 ΔH = 83.7 kJ 1⁄2N2 + 1⁄2O2 ---> NO
1. 1 answer
2. 128 views
In a coffee cup calorimeter, a vigourous reaction took place between potassium solid (0.258 g) and water. The total volume was
1. 1 answer
2. 166 views
Calculate the root mean speed of oxygen gas O2 at 27.0 oC. (R=8.314 Kg.m3/s2.K.mol)(Molar mass: O= 16 g/mol)
1. 1 answer
2. 135 views
20 g of calcium chloride reacts with 20 g of sodium carbonate to form calcium carbonate and sodium chloride.CaCl2+ Na2CO3 →
1. 1 answer
2. 159 views
What volume of ethanol in a litre (L) having a density of 0.678 g/cm3 can be poured into a graduated cylinder to give 16.28 g of
1. 1 answer
2. 103 views
What happens to the value of ΔH for a thermochemical reaction when the reaction is reversed?
1. 1 answer
2. 98 views
In a constant pressure calorimeter, (cup calorimeter) a reaction occurred between sodium (23.00 g, 1.0mol) and water (1000 mL)
1. 1 answer
2. 118 views
If the weight of an object is 8N on earth and the Earth's gravitational field strength of10 N/kg is acting on the object, what
1. 1 answer
2. 170 views
An electrolytic decomposition reaction is a type of decomposition reaction in which the activation energy for decomposition is
1. 1 answer
2. 197 views
Two gases A and B are placed in container that has a piston. A and B react to form product C. As the reaction occurs, the system
1. 1 answer
2. 141 views
Betagesicis potent medicine for the treatment of painful menstrual periods, migraines, and rheumatoid arthritis.. It is composed
1. 1 answer
2. 133 views
What is the energy required to raise the temperature of 1 g of a substance by loC or 1 K?
1. 23 answers
2. 139 views
A 4.0 L of a gas at a pressure of 205 kPa is allowed to expand to a volume of 16.0 L. Calculate the pressure in atmospheres
1. 1 answer
2. 153 views
A 0.500 L of gases is at 307 K and contains N2 at a pressure of 1.40 atm and O2 at a pressure of 0.24 atm. What is the mole
1. 1 answer
2. 120 views
Use the standard enthalpies of formation values shown in the table below to calculate the enthalpy of the reaction shown below:2
1. 1 answer
2. 178 views
25.0 g of calcium chloride reacts with 25.0 g of sodium carbonate to form calcium carbonate and sodium chloride.CaCl2+ Na2CO3
1. 1 answer
2. 181 views
0.2500 g of a known compound was subjected to combustion. 0.1500 g of water and 0.3664 g of carbon dioxide were produced.
1. 1 answer
2. 169 views
Paul was asked to confirm that the amount of sodium chloride supplied by ITC pharmacy was 20 g. The measurement he obtained on
1. 1 answer
2. 172 views
At the molecular level, how would you describe O2?The molecules are well packed and the molecules move rapidly and do not have a
1. 1 answer
2. 159 views
At the molecular level, how would you describe O2?
1. 1 answer
2. 104 views
Gas in a steel container expands. However, the temperature is kept constant. What will happen to the pressure?
1. 1 answer
2. 104 views
A 1.000 gsample of octane (C8H18) is burned in a bomb calorimeter containing 1200 grams of water. After the reaction, the
1. 1 answer
2. 191 views
The mass of a 4.20-g piece of metal was measured several times. The measured masses were 4.99 g, 4.92 g, 4.98 g,and 4.97 g. How
1. 1 answer
2. 141 views
Dry ice (CO2) 1.28 g was emptied into a 10 L container. The temperature of the container was maintained at 35.1oC.Calculate the
1. 1 answer
2. 150 views
Calculate the percentage composition of sulphur in 5 g of an unknown compound containing 2.60 g of sulphur, 0.50 g of hydrogen,
1. 1 answer
2. 168 views
The empirical formula of a certain acid is CH₂O. Whatis the molecular formula, if the molar mass is 90.0 g/mol?
1. 1 answer
2. 143 views
1.00 mol of NH2 is stored at 77 oC in a 7.00 L container. Use the van der Waals equation to determine the pressure exerted by
1. 1 answer
2. 143 views
If 100 g of H2O is produced from 16 g of H2, What is the % yield of H2O?(Molar mass: H= 1g/mol; O=16 g/mol) H2 + O2 → 2H2O
1. 1 answer
2. 105 views
20 g of calcium chloride reacts with 20 g of sodium carbonate to form calcium carbonate and sodium chloride.CaCl2+ Na2CO3 →
1. 1 answer
2. 191 views
To make beef braai that had been seasoned with a mixture of different herbs and seasoning, Propane gas is used to light a
1. 1 answer
2. 143 views
10 L of 0.25 molof oxygen gas at a temperature of 30 °C was converted to ozone at the same temperature and pressure. Calculate
1. 1 answer
2. 148 views
A reaction produced 94.9 grams of nitrogen dioxide gas. However, the calculated theoretical value indicates that 100.10 grams of
1. 1 answer
2. 148 views
A sample of gas at 3.00 x 103 atm inside a steel tank is cooled from -200 °C to 27 °C. What is the final pressure in mmHg of
1. 3 answers
2. 217 views
A system with an increase in internal energy of 80 J and at the same time has 50 J of work done on it by the surrounding. What
1. 1 answer
2. 100 views
What happens to the volume of a fixed amount of a gas if the pressure is divided by a factor of three at constant temperature?Th
1. 1 answer
2. 124 views
A special gas mixture is used in bacterial growth chambers which contains 5.00% by mass of CO2 and 95.0% O2. If the mole
1. 1 answer
2. 186 views
James mistakenly mixed hexane with dichloromethane and water. If the density of hexane is 661 Kg/m3, the density of
1. 1 answer
2. 162 views
An unknown compound of mass 10.7696 g containing carbon, hydrogen and oxygen was combusted in oxygen producing CO2 (29.5747 g)
1. 1 answer
2. 168 views
The volume of water in a volumetric flask is known to be 100.00± 0.05 mL at 25 degreeC and 1 atmosphere. A student uses a 100
1. 1 answer
2. 170 views
The lungs expand when we breathe in, resulting an increase in the volume and a decrease in pressure. When we breathe out, the
1. 1 answer
2. 119 views
The table below shows some values for standard enthalpy changes of combustion.Substance incrementHc Ө / kJ mol−1 C(s) −394
1. 1 answer
2. 167 views
PAC 110 BASIC CHEMISTRYSkip to main content Course Faculty Details & Actions Roster View everyone in your course Progress
1. 1 answer
2. 174 views
A student performed an analysis of a sample forits calcium content and got the following results: 14.91%,14.89%,14.88%, and
1. 1 answer
2. 163 views
The pressure of a sample of an inert gas reduced significantly from 100 kPa to 30kPa. The temperature increases from 27degreeC
1. 1 answer
2. 130 views
Chicken soup is an example ofPure solution Heterogenous mixture Homogenous mixture Mixture
1. 1 answer
2. 154 views
Lead (II) chloride (PbCl2) are produced from the reaction of 7.000 g of NaCl with 50.400 g of Pb(NO3)2? What is the limiting
1. 1 answer
2. 163 views
The temperature of a chemistry laboratory during summer was recorded to be 29.32 degreeC. A student used a thermometer to
1. 1 answer
2. 200 views
Sonia and Jeans weighed the mass of the same an unknown compound three times and obtained the readings shown in the table. Which
1. 1 answer
2. 177 views
23.780 g of acetaldehyde (CH3CHO) reacts completely with oxygen to produce acetic acid (HC2H3O2) using manganese (II) acaetate
1. 1 answer
2. 132 views
An unknown compound contains 13.04% of hydrogen, 34.78% of oxygen, and 52.17% of carbon by mass. Determine the empirical formula
1. 1 answer
2. 171 views
Calculate the root mean square velocity of theoxygen gas (O2) molecules at 77 °C. (R =8.314 Kg.m²/S².mol.K). (atomic mass of
1. 1 answer
2. 140 views
Calculate the root mean square velocity of theoxygen gas (O2) molecules at 77 °C. (R =8.314 Kg.m²/S².mol.K). (atomic mass of
1. 1 answer
2. 155 views
The principal protein of muscle has a mass of 0.000000000000000001031 gram. Convert the following number to scientific notation
1. 1 answer
2. 129 views
How much of heat is needed to warm 500 g of water from 25 °C near to its boiling point of 99°C? The specific heat of capacity
1. 1 answer
2. 131 views
How much of heat is needed to warm 500 g of water from 25 °C near to its boiling point of 99°C? The specific heat of capacity
1. 1 answer
2. 120 views
A metal carbonate, XCO3 of mass 2.012g was heated resulting in the formation of XO, a metal oxide and carbon dioxide with a mass
1. 1 answer
2. 238 views
When 15.0 g of sodium nitrate (NaNO3) was dissolved in water in a bomb calorimeter, the temperature reduced from 25.00 °C to
1. 1 answer
2. 161 views
An unknown compound has a percent composition of 75.95% C, 17.72% N, and 6.33% H by mass with a molar mass of about 240 g/mol.
1. 1 answer
2. 151 views
An unknown compound has a percent composition of 75.95% C, 17.72% N, and 6.33% H by mass with a molar mass of about 240 g/mol.
1. 1 answer
2. 177 views
How many grams of lead (II) chloride (PbCl2) are produced from the reaction of 7.000 g of NaCl and 50.400 g of
1. 1 answer
2. 185 views
When a 7.50 g sample of solid NaOH dissolves in100.00 g of water in a coffee-cup calorimeter, the temperature rises from 21.6°C
1. 1 answer
2. 175 views
When a flat tyre is filled with with air, the increased volume of air in the flat tyre results in the flat tyre recovering its
1. 1 answer
2. 163 views
A water geyser works by heating cold water. The hot water is then released through an outlet nozzle. If the system and
1. 1 answer
2. 173 views
Sasko bread is made using yeast. Yeast is a living organism that converts the sugar in the bread mixture known as a dough into
1. 1 answer
2. 227 views

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