4. Complete the following equations:
CuCl2 + Na2CO3 → 2 NaCl +............
FeSO4 + BaCl2 →


Cu(NO3)2 + CaCO3

Answers

Answer 1

Answer:

2NaCl + CuCO3

FeCl2 + BaSO4

CuCO3 + Ca(NO3)2

Explanation:

Presumably this is a double replacement reaction.

A+B + C+D A+D + C+B

It seems I may be wrong so please try to work out the problem yourself to double check, keeping in mind the charges of each compound.


Related Questions

True or false? All producers are at the top of the food web

Answers

Answer:

false all producers are at the top of food web

which type of chemical bond would be formed between two elements having electron configuration of 1s2 2s2 2p6 3s2 and 1s2 2s2 2p4​

Answers

The electron configuration
1
s
2
2
s
2
2
p
6
3
s
2
3
p
2
is the element Silicon.
The key to deciphering this is to look at the last bit of information of the electron configuration
3
p
2
.
The '3' informs us that the element is in the 3rd Energy Level or row of the periodic table. The 'p' tells us that the element is found in the p-block which are all of the Groups to the right of the transition metals, columns 13-18. The superscript '2' tells us that the element is found in the 2nd column of the p-block Group 14.

A pressure cooker contains 5.68 L of air at a temperature of 390 4K if the absolute pressure of the air in the pressure cooker is 205 Pa how many moles of air are in the cooker

Answers

Answer:

3.59x10⁻⁴ mol

Explanation:

Assuming ideal behaviour we can solve this problem by using the PV=nRT formula, where:

P = 205 PaV = 5.68 Ln = ?R = 8314.46 Pa·L·mol⁻¹·K⁻¹T = 390.4 K

We input the data given by the problem:

205  Pa * 5.68 L = n * 8314.46 Pa·L·mol⁻¹·K⁻¹ * 390.4 K

And solve for n:

n = 3.59x10⁻⁴ mol

What are the laws and calculations governing gas behavior?

Answers

Answer:

Laws governing gas behavior.

Explanation:

Boyle's law:

It relates the pressure and volume of an ideal gas at a constant temperature.

According to this law:

"The volume of a fixed amount of gas at constant temperature is inversely proportional to its pressure".

[tex]P \alpha V[/tex].

Charle's law:

It relates the volume and absolute temperature of an ideal gas at a constant pressure.

According to this law:

"The volume of a fixed amount of gas at constant pressure is directly proportional to its absolute temperature".

[tex]V \alpha T[/tex].

Avogadro's law:

According to this law:

equal volumes of all gases under the same conditions of temperature and pressure contain, an equal number of moles.

[tex]V \alpha n[/tex].

Ideal gas equation:

By combining all the above-stated gas laws, this equation is formed as shown below:

[tex]V \alpha \frac{nT}{P} \\=> V= R. nT/ P\\=>PV=nRT[/tex]

R is called universal gas constant.

It has a value of 0.0821L.atm.mol-1.K-1.

Answer:

Boyle's law, Charle's law,  Guy Lussac's law and Avogadro's law

Explanation:

All the gases behaves similarly when the environment conditions are normal. But when the physical condition changes like when the pressure, volume or temperature changes, the gas behaves differently and shows a deviation.

The number of gas laws are :

Boyle's Law

Boyle's law states that when the temperature remaining constant, the pressure of the gas varies inversely to the volume of the gas.

i.e.   [tex]P \propto \frac{1}{V}[/tex]

Charle' law

Charle's law states that when pressure is constant, the temperature of a gas is directly proportional to the volume.

i.e. , [tex]$T \propto V$[/tex]

Gay Lussac's law

Gay - Lussa law states the volume and the mass of the pressure of the gas is directly proportional to the  temperature of the gas.

i.e. P.T = constant

Avogadro's law

It states that under the conditions of same pressure as well as temperatures, the gases having equal volumes will have same numbers of molecules.

i.e. [tex]\frac{V_1}{n_1}=\frac{V_2}{n_2}[/tex] = constant

Which of the following explains the high boiling
point of water?
a Surface tension
b Polarity
C Capillary action
d Hydrogen bonding

Answers

Answer:

The correct answer is - d. hydrogen bonding.

Explanation:

Water has strong hydrogen bonds between its molecules that require a very high amount of energy in order to break. Water molecules are joined together or bound with a strong intermolecular force called hydrogen bonds.

These bonds require more kinetic energy which means more temperature or heat in order to break the bonds and turn into steam and this is the reason it has a high boiling point.

20ml of water is mixed with 40gm of fine powder. Calculate the concentration of the solution obtained.

Answers

Answer:

[tex]\%m=66.7\%[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to calculate the concentration of the solution obtained, by knowing 20 mL of water are the same to 20 g and therefore the mass of the solution is 40g+20g=60g.

Next, we apply the following equation to obtain the required concentration:

[tex]\%m=\frac{40g}{60g} *100\%\\\\\%m=66.7\%[/tex]

Regards!

Rocks are classified as igneous, metamorphic, or sedimentary according to

Answers

Answer:

D. the minerals they contain

Hope this answer is right!!

Determine the number of significant digits in each number and list the specific significant digits. 1. 306,000 2. 0.0073 3. 39.9999 4. 25.00 5. 40,000,021 6. 45,250.0 7. 0.00011 8. 420.030700

Answers

Answer:

1. 306,000: three significant figures because the last three zeros are not preceded by a decimal point.

2. 0.0073: two significant figures because the the leftmost zeros are not significant.

3. 39.9999: six significant figures because all these numbers are nonzero digits.

4. 25.00: four significant figures because right-handed zeros, after a decimal point, are significant.

5. 40,000,021: eight significant figures because intermediate zeros are significant.

6. 45,250.0: six significant figures because al the zeros are to the right of the nonzero digits.

7. 0.00011: two significant figures as well as #2.

8. 420.030700: nine significant figures because all the zeros are to the right of the first nonzero digits and after the decimal point.

Explanation:

Hello there!

In this case, by considering the given numbers, we can proceed as follows, by keeping in mind the rules for assigning significant figures:

1. 306,000: three significant figures because the last three zeros are not preceded by a decimal point.

2. 0.0073: two significant figures because the the leftmost zeros are not significant.

3. 39.9999: six significant figures because all these numbers are nonzero digits.

4. 25.00: four significant figures because right-handed zeros, after a decimal point, are significant.

5. 40,000,021: eight significant figures because intermediate zeros are significant.

6. 45,250.0: six significant figures because al the zeros are to the right of the nonzero digits.

7. 0.00011: two significant figures as well as #2.

8. 420.030700: nine significant figures because all the zeros are to the right of the first nonzero digits and after the decimal point.

Regards!

Calculate the amount of heat required to completely sublime 55.0 g of solid dry ice CO2 at its sublimation temperature. The heat of sublimation for carbon dioxide is 32.3 kj mol

Answers

Answer:

40.4 kJ

Explanation:

Step 1: Given data

Mass of CO₂ (m): 55.0 gHeat of sublimation of CO₂ (ΔH°sub): 32.3 kJ/mol

Step 2: Calculate the moles corresponding to 55.0 g of CO₂

The molar mass of CO₂ is 44.01 g/mol.

n = 55.0 g × 1 mol/44.01 g = 1.25 mol

Step 3: Calculate the heat (Q) required to sublimate 1.25 moles of CO₂

We will use the following expression.

Q = n × ΔH°sub

Q = 1.25 mol × 32.3 kJ/mol = 40.4 kJ

The value of ΔH° for the reaction below is -6535 kJ. ________ kJ of heat are released in the combustion of 16.0 g of C6H6 (l)?

2C6H6 (l) + 15O2 (g) → 12CO2 (g) + 6H2O (l)

Answers

Answer:

the value of H° is below -6535 kj. +6H2O

Explanation:

6H2O answer solved

For the given reaction, 2 moles of C₆H₆ the heat energy released is - 6535 KJ. Then, for 16 g of the compound or 0.205 moles needs 669.83 KJ of heat released in combustion.

What is combustion ?

Combustion is a chemical reaction that occurs between a fuel and an oxidizing agent, typically oxygen, resulting in the release of heat, light, and various combustion products, such as carbon dioxide and water vapor.

The process of combustion involves a rapid and exothermic (heat-releasing) oxidation reaction that produces a flame, which is visible in many cases.

Here, 2 moles of the hydrocarbon releases - 6535 KJ of energy.

molar mass of C₆H₆ = 78 g/mol

then no.of moles in 16 g = 16 /78 = 0.205 moles.

then energy released by 0.205 moles  = 0.205 moles × 6535 KJ /2 moles = 669.83 kJ

Therefore, the heat energy released by 16 g of the compound in combustion is 669.83 kJ.

Find more on combustion :

https://brainly.com/question/13153771

#SPJ2

how old was the oldest animal fossil
help thx​

Answers

Answer:

the Rhyniognatha hirsti

Explanation:

at age 400 million years old

Please help me, it’s my last try

Answers

Answer:

Group 1A: alkali metals, or lithium family.

Group 2A: alkaline earth metals, or beryllium family.

Group 7A: the manganese family.

Group 8A: the iron family.

Explanation:

Answer:

1A: Alkali Metals

2A: Alkaline Earth Metals

7A: Halogens

8A: Noble Gases

Doc. No.
QMS
Rev. Date
1. In the reaction
P
> M + N
a) The reactants are:
b) The products are:​

Answers

Answer: In the reaction:

a) The reactants are: P

b) The products are: M and N

Explanation:

The given reaction equation is as follows.

[tex]P \rightarrow M + N[/tex]

Reactants are the species present on the left side on an arrow in a chemical reaction equation.

On the other hand, products are the species which are present on the right side of an arrow in a chemical reaction equation.

Hence, in the given reaction equation P is the reactant. Whereas M and N are the products.

Thus, we can conclude that in the reaction:

a) The reactants are: P

b) The products are: M and N

Describe the buffer capacity of the acetic acid buffer solution in relation to the addition of both concentrated and dilute acids and bases. Reference the results in Data Tables 1,2,3, and 4 in your answer.

Answers

Answer:

The more concentrated acetic acid buffer has a better buffer capacity because requires more moles of acid or base to change the pH than a more diluted acetic acid buffer.

Explanation:

Buffer capacity is defined as the moles of an acid or base that are needed to change the pH of a buffer in 1 unit.

A more concentrated solution of acetic buffer contains more moles of the acid per liter of solution. A solution that contains more moles of the acetic ion or the acetic acid requires more moles of base or acid to change the pH, that means:

The more concentrated acetic acid buffer has a better buffer capacity because requires more moles of acid or base to change the pH than a more diluted acetic acid buffer.

HELPPPPPPPPPPPPMEEEEEEEEEE

Answers

Answer:

25%

Explanation:

Cystic fibrosis is a recessive allele, meaning that the child must be aa to suffer the symptoms. Only 1/4 of the paired alleles is aa, so the probability of getting cystic fibrosis would be 25%.

75% is the chance because a capital letter means it’s a dominant allele meaning it’s a possible outcome there’s 3 capital letter for which it’s 75 since each box is worth 25

13. What does the Law of Conservation of Mass state?

Answers

The law of conservation of mass states that mass can neither be created or destroyed in a chemical reaction.

Kristy finds the mass of an object to be 20 grams and the volume to be 10 mL. What is the density of the object? (don't send me links, just give a straight answer)

Answers

the answer is 2g/ml i believe as you have to do the mass divided by the volume

The table shows the recipe and the available ingredients for making the maximum possible number of sandwiches.



Making Sandwiches

Recipe for One Sandwich:
2 cheese slices, 1 ham slice, 2 bread slices

Ingredients Available:
12 cheese slices, 10 ham slices, 12 bread slices

If the ingredients represent reactants of a chemical reaction, which of the following represents the leftover reactant?

A. 2 ham slices

B. 4 ham slices

C. 2 cheese slices

D. 4 cheese slices

Answers

Answer:

B. 4 ham slices

Explanation:

A chemical reaction involves one or more substances known as reactants combining chemically to give one or more substances known as products.

Reactants in chemical reactions combine in definite mole or mass ratios to give products. Therefore, when one substance is present in excess of what is required to combine with another to form products, that substance is known as the excess reagent. The other substance which is present in a smaller amount and which when used up, the reaction stops is known as the limiting reagent.

From the illustration of the sandwiches in the question, the recipe for one sandwich represents the chemical equation of a reaction. The equation form is given below:

2 cheese slices + 1 ham slice + 2 bread slices ---> 1 sandwich

The ratio of the reactant is 2 : 1 : 2

From the available ingredients, 12 cheese slices, 10 ham slices, 12 bread slices.

12 cheese slices will require 6 ham slices and 12 bread slices to produce 6 sandwiches.

However, since there are 10 ham slices, 4 ham slices will be left over unused. This is the excess or leftover reactant.

Answer:

B. 4 ham slices

Explanation:

Got it right on the test

5.96 g of ammonia reacts completely according to the following reaction:
2 NH, (g) + Co, (g) → CN,OH, (s) + H20 (1)
(a) What is the theoretical yield of urea (CN,OH,) for this reaction?
(b) If 13.74 g of urea are produced, what is the percent yield for this equation?

please show work, will give brainliest

Answers

Explanation:

this explanation may help u to understand:)

In the reaction below, what is the limiting reactant when 1.24 moles NH3 of reacts with 1.79 moles of NO?

4NH_3 + 6NO (right arrow) 5N_2 + 6H_2O

1. NO
2. H_2O
3. NH_3
4. N_2

Answers

Answer:

Option 1. NO

Explanation:

The balanced equation for the reaction is given below below:

4NH₃ + 6NO —> 5N₂ + 6H₂O

From the balanced equation above,

4 moles of NH₃ reacted with 6 moles of NO.

Finally, we shall determine the limiting reactant. This can be obtained as follow:

From the balanced equation above,

4 moles of NH₃ reacted with 6 moles of NO.

Therefore, 1.24 moles of NH₃ will react with = (1.24 × 6)/4 = 1.86 moles of NO

From the calculation made above, we can see that a higher amount of NO (i.e 1.86 moles) than what was given (i.e 1.79 moles) is needed to react completely with 1.24 moles of NH₃.

Therefore, NO is the limiting reactant and NH₃ is the excess reactant.

Thus, the 1st option gives the correct answer to the question

Answer:

1. NO .

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to identify the limiting reactant by simply calculating the moles of any product, say N2, via the moles of each reactant and including the corresponding mole ratio (4:5 and 6:5):

[tex]1.24molNH_3*\frac{5molN_2}{4molNH_3}=1.55molN_2 \\\\1.79molNO*\frac{5molN_2}{6molNO}=1.50molN_2[/tex]

Thus, since NO yields the fewest moles of N2 product, we infer it is the limiting reactant.

Regards!

Aluminum metal reacts with oxygen gas in a combination reaction that forms a product that coat the metal preventing it from further oxidation. Which of the following is the correct balanced equation for the reaction?
a. Al(s) + 302(g) → 2903(s).
b. 2Al(s) + O2(g) → 2A10(s).
c. AI(s) + O2(g) → AIO (s).
d. 4Al(s) + 3O2(g) →2Al2O3.
e. 3Al(s) + O2 → Al3O2.

Answers

Answer:

d. 4 Al(s) + 3 O₂(g) → 2 Al₂O₃(s)

Explanation:

Aluminum metal reacts with oxygen gas in a combination reaction that forms a product that coats the metal preventing it from further oxidation: aluminum oxide. Aluminum is a cation with charge 3+ (Al³⁻) and oxide is an anion with charge 2- (O²⁻). Thus, the neutral compound aluminum oxide has the chemical formula Al₂O₃. The unbalanced chemical equation is:

Al(s) + O₂(g) → Al₂O₃(s)

We can balance using the trial and error method. First, we will balance O atoms by multiplying Al₂O₃ by 2 and O₂ by 3.

Al(s) + 3 O₂(g) → 2 Al₂O₃(s)

Finally, we get the balanced equation by multiplying Al by 4.

4 Al(s) + 3 O₂(g) → 2 Al₂O₃(s)

It took 2.30 minutes using a current of 3.00 A to plate out all the copper from 0.300 L of a solution containing Cu2 . What was the original concentration of Cu2

Answers

Answer:

7.16 × 10⁻³ M

Explanation:

Let's consider the reduction reaction of copper during the electroplating.

Cu²⁺(aq) + 2 e⁻ ⇒ Cu(s)

We can calculate the moles of Cu²⁺ present in the solution using the following relations.

1 A = 1 C/s.1 min = 60 s.1 mole of electrons has a charge of 96486 C (Faraday's constant).1 mole of Cu²⁺ is reduced when 2 moles of electrons are gained.

The moles of Cu²⁺ reduced are:

[tex]2.30 min \times \frac{60s}{1min} \times \frac{3.00C}{s} \times \frac{1mole^{-} }{96486C} \times \frac{1molCu^{2+} }{2mole^{-} } = 2.15 \times 10^{-3} molCu^{2+}[/tex]

[tex]2.15 \times 10^{-3} moles[/tex] of Cu²⁺ are in 0.300 L of solution.

[Cu²⁺] = 2.15 × 10⁻³ mol/0.300 L = 7.16 × 10⁻³ M

Copper sulfate is made of one copper (Cu) atom, one sulfur (S) atom, and four oxygen (O) atoms. Write the chemical formula correctly.

Answers

The chemical formula for copper sulfate is CuSO4

Having enough folic acid in your system by the early weeks of pregnancy is critical to prevent spina bifida.

Answers

Answer:

Yes.

Explanation:

Yes, enough folic acid in the body by the early weeks of pregnancy helps to prevent spina bifida. The body of woman uses folate during the pregnancy which produces red and white blood cells that help your baby to grow. Folate also lowers the risk of neural tube defect (NTD) in the unborn baby. Neural tube defect (NTDs) are the serious birth defects that greatly affect the spinal cord, brain and skull of the baby.

calculate the maximum theoretical percent recovery from the recrystallization of 1.00g of benzoic acid

Answers

Answer:

The maximum theoretical percent recovery from the recrystallization of 1.00 g of benzoic acid from 15 mL of water = 94.9%

Note: The question is incomplete. A similar but complete question is given below:

The solubility of benzoic acid in water is 6.80g per 100mL at 100 degrees C and 0.34 g per 100mL at 25 degrees C.

Calculate the maximum theoretical percent recovery from the recrystallization of 1.00 g of benzoic acid from 15 mL of water, assuming the solution is filtered at 25 degrees C.

Explanation:

Solubility of benzoic acid in water at 100 degrees C = 6.80g per 100mL

Solubility of benzoic acid in water  at 25 degrees C =  0.34 g per 100mL

Mass of benzoic acid to be theoretically recovered from 100 mL of water = 6.80 g - 0.34 g = 6.46 g

At 25 degrees;

0.34 g of benzoic acid is present in 100 mL of water

x g of  benzoic acid will be present in 15 mL of water

x = 0.34 × 15 / 100 = 0.051 g

Mass of benzoic acid to be theoretically recovered from 25 mL of water = 1.00 g - 0.051 g = 0.949 g

Maximum theoretical percent recovery = (mass recovered / original mass dissolved) x 100%

Maximum theoretical percent recovery =  (0.949 / 1.00) × 100% = 94.9 %

Therefore, the maximum theoretical percent recovery from the recrystallization of 1.00 g of benzoic acid from 15 mL of water = 94.9%

Describe the three freezing points. Is there a relationship between the amount of solute in the solution and the freezing temperature

Answers

Answer:

The three freezing points will all be slightly different. It is given that a water solution has a freezing point of zero degrees Celsius, so water would have a freezing temperature below that. Salt will lower the freezing point, the more that is added.

Explanation:

g Suppose you are titrating an acid of unknown concentration with a standardized base. At the beginning of the titration, you read the base titrant volume as 1.84 mL. After running the titration and reaching the endpoint, you read the base titrant volume as 27.30 mL. What volume, in mL, of base was required for the titration?

Answers

Answer:

25.46 mL

Explanation:

In a titration we use the volume and concentration of a solution to determine the previously unknown concentration of other solution. Let's consider the titration of an acid of unknown concentration with a standardized base (a base whose concentration we know). The generic neutralization reaction is:

HA + BOH ⇒ BA + H₂O

The base is in the buret and we will add it to the acid until the equivalence point is reached. The volume of base used is equal to the difference between the final reading of the buret and the initial reading of the buret.

V = 27.30 mL - 1.84 mL = 25.46 mL

Identify each of the following as endothermic or exothermic.

a. Water in a pond evaporates.
b. Methane gas burns on a stove top.
c. Water freezes to form ice.
d. Energy flows from the system to the surroundings.
e. Energy flows from the surroundings to the system.

Answers

Answer:

Identify each of the following as endothermic or exothermic.

a. Water in a pond evaporates.

b. Methane gas burns on a stovetop.

c. Water freezes to form ice.

d. Energy flows from the system to the surroundings.

e. Energy flows from the surroundings to the system.

Explanation:

An exothermic reaction is the one in which heat energy is released.

An endothermic reaction is one in which heat energy is absorbed.

a. Water in a pond evaporates.

This process absorbs heat energy.

Hence, this is an example of an endothermic process.

b. Methane gas burns on a stovetop and release heat energy and hence this is an example of an exothermic reaction.

c. Water freezes to form ice.

In this process heat energy is released.So this is an example of exothermic reaction.

d. Energy flows from the system to the surroundings.

That means heat energy is released into the surroundings.

So, this is an example of exothermic process.

e. Energy flows from the surroundings to the system.

That means energy is absorbed by the system.

So, it is an endothermic process.

Refer to your completed Table 1d of the recitation guide of ionic compound naming rules to determine whether this statement is true or false. A Roman numeral in a compound name tells you how many of that ion appear in the formula. Select one: True False

Answers

Answer:

False

Explanation:

Roman numerals are seen in the names of several compounds. They often appear immediately after the name of central atom in the molecule.

These Roman numerals are used to depict the oxidation state of the central atom in the molecule and not to show how many of that ion appear in the formula.

For instance, in carbon IV oxide, the Roman numeral IV shows that the central atom in the compound-carbon is in the +4 oxidation state.

someone answer please​

Answers

uhhh maybe decreases

Answer:

A

Explanation:

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