Question

У меня будет экзамен по химии,а я понятия не имею как и что вычислять,научите меня Вычислите,какое количество соли _______обрзуется из______моль (заместо_____ учитель напишет что то) Вычислите массу и объём___моль Вычислите,какое количество вещества соли_____,потребуется для получения____моль Расчитайте ,какое количество вещества _______ получится из_____моль Какое количество вещества соответствует__________газа___Какова его масса? Вычислите ,какое количество вещества____________образуется из______моль Вычислите,какое количество вещества соответствует_________Каков его объём? Вычислите какое количество вещества_________необходимо для получения____моль И как осуществлять превращения? помогите пожалуйста

Answer 1

Сдесь просто надо значть формулы

самая главная формула это m= M * n

где m масса вещества, кг, г

M молярная масса вещества ( она вычисляется по таблице менделеева, например возьмем CuO оксид меди (II) молярная масса меди = 64, находи это в таблице Менделеева, под порядковым номером, а у кислорода 16, а в общем их молярная масса M=64+16=80 Г/моль, измеряется либо в г/моль, либо в кг/ моль, зависит от условия задачи( например если тебе дана масса вещества в кг, то и молярную пишешь в кг, а так чаще всего в г/моль, с газами не много подругому, у них обьем, и обьем молярный равен 22Б4 л/моль, а место масыы в формуле ты обычный объем подставляешь)

n - количество вещества, измеряется в молях

из первой формулы можно выразить n

n= m/ M

удачи

Answer 2

сначала пишешь уравнения реакций. и обязательно с коэффициентами

 

потом с помощбю пропорции находишь моль одного одного в-ва из другого

 

Например, у тебя уравнение, и сказано, что разложилось 10 моль воды (Н2О). тебе нужно найти сколько моль кислорода получилось

 

 

2H2O=2H2 + O2

 

подчеркиваешь, что тебе нужно (вода и кислород) и подписываешь их химическое кол-во под подчеркнутым (оно соотвествует значению коэффциента)

 

2H2O=2H2 + O2

2 моль         1 моль

 

затем надписываешь известное и ставишь х над неизвестным

 

10 моль            х

2H2O=2H2 + O2

2 моль         1 моль

 

у тебя выходит пропория:

 

$\frac {10}{2}=\frac {x}{1}$

 

решаешь ее и находишь хим. кол-во требуемого в-ва (в нашем примере ксилорода), то есть 5 моль

 

вот и все!

 

ну а если сказано найти массу, то нужно знать формулу:

 

$m = n* M$

m - масса

n - хим. количество (мы его находили)

M- молярная масса (например у воды 18, у кислорода 32)

 

 

ну а если сказано найти объем, то нужно знать формулу:

 

$V = n* V_m$

V - требуемый объем

n - хим. количество (мы его находили)

Vm- молярный объем (он всегда равен 22,4 дм3/моль)

 

Answer 3

Calculating the Amount of Salt Formed from a Given Number of Moles

To calculate the amount of salt formed from a given number of moles, you need to know the balanced chemical equation for the reaction. Without the specific chemical equation provided, I won't be able to give you an exact answer. However, I can guide you through the general process of calculating the amount of salt formed.

1. Start with the balanced chemical equation for the reaction. 2. Identify the stoichiometric coefficients of the reactants and products in the equation. These coefficients represent the mole ratios between the reactants and products. 3. Determine the number of moles of the substance you have information about (either the reactant or the product). 4. Use the mole ratios from the balanced equation to calculate the number of moles of the other substance.

For example, let's say the balanced chemical equation is:

2A + 3B → 4C + D

If you know the number of moles of substance A, you can use the mole ratio to calculate the number of moles of substance C formed. In this case, the mole ratio between A and C is 2:4, so for every 2 moles of A, 4 moles of C are formed.

Please provide the specific balanced chemical equation for the reaction you are studying, and I'll be able to guide you through the calculations more accurately.

Calculating the Mass and Volume of a Given Number of Moles

To calculate the mass and volume of a given number of moles, you need to know the molar mass and density of the substance. Without this information, I won't be able to give you an exact answer. However, I can guide you through the general process of calculating the mass and volume.

1. Determine the molar mass of the substance. The molar mass is the mass of one mole of the substance and is expressed in grams per mole (g/mol). 2. Multiply the number of moles by the molar mass to calculate the mass of the substance. 3. If you also have the density of the substance, you can use the formula: density = mass/volume. Rearrange the formula to solve for volume: volume = mass/density. Multiply the mass by the reciprocal of the density to calculate the volume.

Please provide the specific substance you are studying, along with its molar mass and density if available, and I'll be able to guide you through the calculations more accurately.

Calculating the Amount of Substance Required for a Given Number of Moles

To calculate the amount of substance required for a given number of moles, you need to know the balanced chemical equation for the reaction. Without the specific chemical equation provided, I won't be able to give you an exact answer. However, I can guide you through the general process of calculating the amount of substance required.

1. Start with the balanced chemical equation for the reaction. 2. Identify the stoichiometric coefficients of the reactants and products in the equation. These coefficients represent the mole ratios between the reactants and products. 3. Determine the number of moles of the substance you have information about (either the reactant or the product). 4. Use the mole ratios from the balanced equation to calculate the number of moles of the other substance.

For example, let's say the balanced chemical equation is:

2A + 3B → 4C + D

If you know the number of moles of substance C, you can use the mole ratio to calculate the number of moles of substance B required. In this case, the mole ratio between C and B is 4:3, so for every 4 moles of C, 3 moles of B are required.

Please provide the specific balanced chemical equation for the reaction you are studying, and I'll be able to guide you through the calculations more accurately.

Calculating the Mass and Volume of a Given Amount of Gas

To calculate the mass and volume of a given amount of gas, you need to know the molar mass of the gas and the ideal gas law. The ideal gas law is expressed as:

PV = nRT

Where: - P is the pressure of the gas (in units of pressure, such as atm or Pa) - V is the volume of the gas (in units of volume, such as liters or m^3) - n is the number of moles of the gas - R is the ideal gas constant (0.0821 L·atm/(mol·K) or 8.314 J/(mol·K)) - T is the temperature of the gas (in units of temperature, such as Kelvin)

To calculate the mass of the gas, you can use the formula: mass = molar mass × number of moles.

Please provide the specific gas you are studying, along with its molar mass, pressure, volume, and temperature if available, and I'll be able to guide you through the calculations more accurately.

Converting Between Moles and Volume

To convert between moles and volume, you need to know the molar volume of the gas at a specific temperature and pressure. The molar volume is the volume occupied by one mole of gas at a given temperature and pressure.

The molar volume of an ideal gas at standard temperature and pressure (STP) is approximately 22.4 liters per mole (L/mol). This means that at STP, one mole of any ideal gas occupies a volume of 22.4 liters.

To convert moles to volume, multiply the number of moles by the molar volume. To convert volume to moles, divide the volume by the molar volume.

Please provide the specific gas you are studying, along with the temperature and pressure conditions, and I'll be able to guide you through the calculations more accurately.

Performing Chemical Transformations

To perform chemical transformations, you need to understand the specific reaction you are studying and follow the principles of stoichiometry. Stoichiometry is the study of the quantitative relationships between reactants and products in a chemical reaction.

Here are the general steps to perform chemical transformations:

1. Write the balanced chemical equation for the reaction. 2. Identify the stoichiometric coefficients of the reactants and products in the equation. These coefficients represent the mole ratios between the reactants and products. 3. Determine the number of moles of the substance you have information about (either the reactant or the product). 4. Use the mole ratios from the balanced equation to calculate the number of moles of the other substance. 5. If necessary, convert the number of moles to mass or volume using the molar mass or molar volume of the substance. 6. Follow any specific instructions or conditions given in the problem or experiment.

Please provide the specific chemical transformation you are studying, and I'll be able to guide you through the calculations and process more accurately.