Amount of Substance Flashcards

How do you convert Celsius to Kelvin?

To convert Celsius to Kelvin, you add 273 to the Celsius temperature.
Export

This text is tab separated and can be imported into various flashcard apps.
How do you convert Celsius to Kelvin?	To convert Celsius to Kelvin, you add 273 to the Celsius temperature.
Describe the process of converting quantities between different substances using a balanced equation.	The process involves using the stoichiometric ratios from a balanced equation to convert between moles, mass, volume, concentration, and other units of measurement.
Do equal volumes of gases under the same conditions contain the same number of molecules?	Yes, equal volumes of gases under the same conditions of temperature and pressure contain the same number of molecules (or atoms if the gas is monatomic).
How can you calculate the pressure of a gas mixture in a flask at a given temperature?	You can calculate the pressure of a gas mixture in a flask at a given temperature by using the equation P1V1 = P2V2, where P1 and V1 are the initial pressure and volume, and P2 and V2 are the final pressure and volume.
Define reacting volumes of gas.	Reacting volumes of gas refers to the volumes of gases involved in a chemical reaction, which can be calculated using the balanced equation and the concept of stoichiometry.
What is the ideal gas equation?	The ideal gas equation is PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature.
Describe the process of changing the conditions of a gas.	Changing the conditions of a gas involves altering the temperature, pressure, or volume of the gas.
Describe how to calculate the mass of a gas using the ideal gas equation.	To calculate the mass of a gas, you multiply the number of moles (n) by the molar mass (Mr) of the gas.
Define moles in the context of the ideal gas equation.	Moles represent the amount of substance and are used to calculate the number of gas particles in a given sample.
What are the three types of equations that can be used to convert quantities between different substances?	The three types of equations are: 1) For pure solids, liquids, and gases; 2) For gases; 3) For solutions.
What are the units of pressure, volume, and temperature in the ideal gas equation?	The unit of pressure is Pascal (Pa), the unit of volume is cubic meter (m³), and the unit of temperature is Kelvin (K).
What are the hazards associated with stronger acids and alkalis?	Stronger acids and alkalis can be corrosive and may cause harm to the eyes. It is important to wear goggles when handling them to protect the eyes from any potential damage.
Describe the safety precautions for handling dilute acid and alkalis.	When handling dilute acid and alkalis, it is important to wear goggles to protect the eyes. These substances can be irritants and may cause harm if they come into contact with the skin. It is also important to wash hands after use to avoid any potential harm.
How does diluting a solution affect its concentration?	Diluting a solution will not change the amount of moles of solute present but increase the volume of solution, and hence the concentration will lower.
What is the formula for calculating dilutions?	Moles = volume X concentration. If the amount of moles does not change, then the new diluted concentration is equal to the original concentration multiplied by the original volume, divided by the new diluted volume.
Describe the process of diluting a solution using a volumetric pipette.	Using a volumetric pip is more accurate than a measuring cylinder because it has a smaller uncertainty. Pipette 25cm³ of original solution into a 250cm³ volumetric flask and make up to the mark with distilled water using a dropping pipette for the last few drops. Invert the flask several times to ensure a uniform solution.
What is a titration?	A method used to determine the concentration of a solution by reacting it with a solution of known concentration.
What is the purpose of diluting a sample in a volumetric flask before titration?	The purpose of diluting a sample in a volumetric flask before titration is to ensure that the volume of the sample is accurately known and to make it easier to measure and transfer a precise volume of the sample for titration.
Define the term 'back titration'.	Back titration is a technique used in analytical chemistry to determine the amount of a substance by reacting it with an excess of another substance and then titrating the excess.
How can distilled water be used during a titration?	Distilled water can be added to the conical flask to wash the sides and ensure all the reactants are properly mixed.
Define an indicator in the context of titrations.	A substance that changes color at or near the equivalence point of a titration, indicating the completion of the reaction.
What are some safety precautions to take during a titration?	Wear eye protection and gloves, rinse equipment before and after use, and immediately wash any spills.
Describe the method for carrying out a titration.	Add a few drops of indicator to the solution being titrated, then slowly add the titrant solution from a burette until the indicator changes color.
Define the unit of mass concentration.	The unit of mass concentration is g dm-3, which represents the mass of solute dissolved in 1 dm³ of solution.
How is percentage atom economy calculated?	Percentage atom economy is calculated by dividing the total mass of atoms in the desired product by the total mass of atoms in all the reactants, and multiplying by 100.
Define percentage yield in a chemical reaction.	Percentage yield is a of the efficiency of a chemical reaction, calculated by dividing the actual yield (mass of useful products by the theoretical yield (mass of products calculated based on stoichiometry) and multiplying by 100.
Describe the concept of limiting and excess reactants.	Limiting reactant refers to the reactant that is completely consumed in a chemical reaction, limiting the amount of product that can be formed. Excess reactant refers to the reactant that is present in excess and is not completely consumed.
Define stoichiometric ratios.	Stoichiometric ratios are the mole ratios obtained from a balanced equation that represent the relationship between the amounts of reactants and products in a chemical reaction.
How can you convert moles of a substance into the quantity of another substance asked for?	You can use the relevant equation (based on the type of substances involved) and the balanced equation to convert moles of the initial substance into moles of the second substance.
What is the general method for calculating an empirical formula?	The general method involves dividing each mass (or % mass) by the atomic mass of the element and then dividing the answers by the smallest one to obtain whole numbers.
Describe the definition of an empirical formula.	An empirical formula is the simplest ratio of atoms of each element in a compound.
Do density calculations work for solids, liquids, and gases?	Yes, density calculations can be used for solids, liquids, and gases. However, they are usually used with pure liquids to determine mass from a measured volume.
Describe density.	Density is the mass of a substance per unit volume. It is usually given in grams per cubic centimeter (g/cm^3).
How can Avogadro's Constant be used?	Avogadro's Constant can be used to calculate the number of atoms, molecules, or ions in a given amount of substance.
Define the mole.	The mole is the amount of substance that contains Avogadro's Constant (6.022 x 10^23) particles.
Describe Avogadro's Constant.	Avogadro's Constant is the number of particles (atoms, molecules, ions) in one mole of a substance, which is approximately 6.022 x 10^23.
How many significant figures should be used in the answer when calculating moles?	The answer should have the same number of significant figures as the data given in the question.
How can the molecular formula be deduced from the empirical formula?	By determining how many times the mass of the empirical formula fits into the relative molecular mass (Mr) of the compound.
How do you convert cm³ to dm³?	To convert cm³ to dm³, divide by 1000.
What is the unit of concentration?	The unit of concentration is mol dm-3 or M.
How is relative molecular mass defined?	Relative molecular mass is the average mass of a molecule compared to one twelfth of the mass of one atom of carbon-12.
What is the definition of relative atomic mass?	Relative atomic mass is the average mass of one atom compared to one twelfth of the mass of one atom of carbon-12.
Define Avogadro's Number.	Avogadro's Number is the number of atoms in 12 grams of carbon-12, which is approximately 6.022 X 10^23.
What is a solution?	A mixture formed when a solute dissolves in a solvent.
What happens when soluble ionic solids dissolve in water?	When soluble ionic solids dissolve in water, they dissociate into separate ions, leading to a difference in concentration between the solute and the ions.
Describe the process of making a solution.	To make a solution, weigh the required mass of solid, transfer it to a beaker, add distilled water, stir to dissolve the solid, transfer the solution to a graduated flask, and make up to the mark with distilled water.
How can concentration in mol dm-3 be converted to g dm-3?	To convert concentration measured in mol dm-3 into concentration measured in g dm-3, multiply by the molar mass (Mr) of the substance.
What is mass concentration?	Mass concentration is the measurement of the mass of solute per volume of solution, expressed in g dm-3.
Define the unit of volume.	dm³ or litre.
What is the unit of molar concentration?	Mol dm-3 or M.
How is molar concentration calculated?	By dividing the amount in moles of the solute by the volume of the solution.
Describe the concept of a mole.	The mole is the amount of substance in grams that has the same number of particles as there are atoms in 12 grams of carbon-12.
Define anhydrous copper (II) nitrate(V).	Anhydrous copper (II) nitrate(V) refers to copper (II) nitrate(V) without any water of crystallisation.
How can the mass loss in thermal decomposition reactions be measured using a crucible?	Heating in a crucible can be used to measure mass loss in various thermal decomposition reactions.
What is the purpose of the lid in the crucible during the heating process?	The lid improves the accuracy of the experiment as it prevents loss of solid from the crucible but should be loose fitting to allow gas to escape.
Describe the process of removing water of crystallisation from calcium sulfate crystals.	The water of crystallisation in calcium sulfate crystals can be removed as water vapour by heating according to the equation: CaSO4.xH2O(s) -> CaSO4(s) + xH2O(g).
What is a hydrated salt?	A hydrated salt contains water of crystallisation.
Define a molecular formula.	A molecular formula is the actual number of atoms of each element in a compound.
Click to copy
Combining packs is currently only available to subscribers.
Print Flashcards

Print Type

Single sided
Double sided
Single Sided - Each row displays the front of a card on the left and its back on the right. Cut along rows, fold at the center, and glue together.
Double Sided - Card fronts are on one page and their corresponding backs on the next. After cutting, the backs match up with their respective fronts.
Rows Per Page

2345678910
1 / 58
Options

Study Mode

Flashcards
Exam
Arrange Cards

Chronological
Random
Share this pack
