Answer:
potentiol or kenetic
Explanation:
2. Energy cycles through ecosystems because it returns to the sun.
True or false
Please help I will give 50 points
Answer:
false
Explanation:
energy does not return to the sun, it returns to the plants or producers. if energy were to return to the sun, it would have to travel though space.
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.
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.
(a) Describe the process by which Nitrogen is obtained from air on a large scale
The element nitrogen exists as a gas and is obtained from air on a large scale by fractional distillation of air.
What is an element?An element is defined as a substance which cannot be broken down further into any other substance. Each element is made up of its own type of atom. Due to this reason all elements are different from one another.
Elements can be classified as metals and non-metals. Metals are shiny and conduct electricity and are all solids at room temperature except mercury. Non-metals do not conduct electricity and are mostly gases at room temperature except carbon and sulfur.
The number of protons in the nucleus is the defining property of an element and is related to the atomic number.All atoms with same atomic number are atoms of same element.
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Intramolecular forces of attraction are important in holding large molecules together.
a. True
b. False
Answer:
False. Intermolecular forces of attraction are important in holding large molecules together.
Explanation:
Within a molecule, atoms are held together by intramolecular forces. That is, intramolecular forces are the attractive forces that hold the atoms or ions that make up chemical substances (elements and compounds) together, forming a chemical bond.
On the other hand, intermolecular forces are those that act on different molecules or ions and that make them attract or repel each other. In other words, intermolecular forces are those that occur between the different molecules of a compound, and cause these molecules or ions to attract or repel each other.
So, intermolecular forces of attraction are important in holding large molecules together.
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.
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.
True or false? All producers are at the top of the food web
Answer:
false all producers are at the top of food web
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
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
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
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/molStep 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
Question 8 (5 points)
(08.02 MC)
A 10 M concentrated stock solution of NaCl was used to prepare 5 liters of diluted 1 M solution. Which of the following statements is true about
the
process used to achieve this required dilution? (5 points)
O a
The volume of stock solution used was less than 0.4 liters.
Oь
The volume of stock solution used was more than 5 liters.
Ос
The volume of the solvent used was less than 0.4 liters.
Od
The volume of the solvent used was less than 5 liters.
Answer:
d . The volume of the solvent used was less than 5 liters.
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to calculate the volume of the stock (initial) solution by using the following equation:
[tex]M_1V_1=M_2V_2[/tex]
Thus, we solve for, V1, which stands for the aforementioned volume of stock solution:
[tex]V_1=\frac{M_2V_2}{M_1}[/tex]
Then, we plug in to obtain:
[tex]V_1=\frac{5L*1M}{10M}\\\\V_1=0.5L[/tex]
Now, since the final volume was 5 L, we can infer that the volume of solvent is 4.5 L and that of the stock solution 0.5 L for a total of 5 L of diluted solution; therefore, the correct reasoning is d . The volume of the solvent used was less than 5 liters.
Regards!
Answer:
The volume of the solvent is less than 5
Explanation:
A worker gets paid 11.33 $/hour. The worker works on average 39.7 hours/week for 48 weeks per year. How much does the worker make in 1.7 years?
Answer:
36704 $
Explanation:
First we calculate how much the worker gets paid in one week:
11.33 $/hour * 39.7 hour/week = 449.80 $/weekThen we calculate how many weeks does the worker work in 1.7 years:
48 week/year * 1.7 years = 81.6 weeksFinally we calculate how much does the worker make in 1.7 years:
449.80 $/week * 81.6 weeks = 36704 $An alkyl groyp has a formula of CxH6, determine the value of x
Answer:
i didnt understand
Explanation:
Answer:
x = 2 (C₂H₆)
Explanation:
The general formula for alkanes is CₓH₂ₓ₊₂
2x + 2 = 6
Simply solve for n:
2x = 4
x = 2
13. What does the Law of Conservation of Mass state?
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)
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.
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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.
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)
A hot air balloon has an air vent that keeps the air pressure inside and outside the same. Allen observes that a hot air balloon rises up when the gas molecules inside it are heated. Which
of the following laws is used to understand the behavior of the gas and why?
a) The high temperature brings the gas molecules closer together according to Charles's law because this law describes how a gas will behave at constant pressure
b) The high temperature makes the gas molecules spread apart according to Charles's law because this law describes how a gas will behave at constant pressure.
c) The high temperature lowers volume according to Boyle's law because this law describes how a gas will behave when the number of moles remains constant.
d) The high temperature ralses volume according to Boyle's law because this law describes how a gas will behave when the number of moles remains constant.
Answer:
B - The high temperature makes the gas molecules spread apart according to Charles's law because this law describes how a gas will behave at constant pressure.
Explanation:
Charle's Law describes the relationship between temperature and volume, where increased temperature leads to increased volume. When volume is increased, that means the gas molecules are more spread apart and have more random motion. Therefore, the answer is B.
The high temperature causes the gas molecules to spread apart according to Charles's law because explain how a gas, behave at constant pressure.
What does Charles law state?The physical principle called Charles' law which states that the volume of a gas equals a constant value many by its temperature as measured on the Kelvin scale.
Volume regaled by a clinched amount of gas is directly proportional to its temperature and pressure if remains steady.
Thus, option "B" is correct, the volume of a gas equals a constant value.
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HELPPPPPPPPPPPPMEEEEEEEEEE
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%.
Describe the three freezing points. Is there a relationship between the amount of solute in the solution and the freezing temperature
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:
anuvia, the trade name for sitagliptin, was introduced in 2006 for the treatment of type 2 diabetes. In what type of orbital does the lone pair on each N atom reside.
Answer: hello your question is poorly written below is the complete question
answer:
For N1 : sp³ orbital
For N2: p orbital
For N3 : p orbital
For N4 : sp² orbital
For N5 : sp² orbital
Explanation:
Determining the type of orbital in which the lone pair on each N atom will reside.
From the configuration attached below we can determine the type of orbital and they are ;
For N1 : sp³ orbital
For N2: p orbital
For N3 : p orbital
For N4 : sp² orbital
For N5 : sp² orbital
A 3.06 gram sample of an unknown hydrocarbon with empirical formula CH2O was found to contain 0.0170 moles of the substance. What are the molecular mass and molecular formula, respectively, of the compound
Answer:
180 amu
C₆H₁₂O₆
Explanation:
Step 1: Determine the molecular mass of the compound
The sample has a mass (m) of 3.06 g and it contains (n) 0.0170 moles. The molar mass M is:
M = m/n = 3.06/0.0170 mol = 180 g/mol
Then, the molecular mass is 180 amu.
Step 2: Determine the molar mass of the empirical formula.
M(CH₂O) = 1 × M(C) + 2 × M(H) + 1 × M(O)
M(CH₂O) = 1 × 12 g/mol + 2 × 1 g/mol + 1 × 16 g/mol = 30 g/mol
Step 3: Determine the molecular formula
First, we will determine "n" according to the following expression.
n = molar mass molecular formula / molar mass empirical formula
n = 180 g/mol / 30 g/mol = 6
The molecular formula is:
n × CH₂O = 6 × CH₂O = C₆H₁₂O₆
someone answer please
Answer:
A
Explanation:
Copper sulfate is made of one copper (Cu) atom, one sulfur (S) atom, and four oxygen (O) atoms. Write the chemical formula correctly.
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?
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
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)
Which of the following explains the high boiling
point of water?
a Surface tension
b Polarity
C Capillary action
d Hydrogen bonding
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.
Copper metal has a specific heat of 0.385 J/g.C. calculate the amount of heat required to raise the temperature of 22.8g of copper metal from 20.0C to 875°C
Answer:
7505.19 J
Explanation:
We'll begin by calculating the change in the temperature of copper. This can be obtained as follow:
Initial temperature (T₁) = 20 °C
Final temperature (T₂) = 875 °C
Change in temperature (ΔT) =?
ΔT = T₂ – T₁
ΔT = 875 – 20
ΔT = 855 °C
Finally, we shall determine the heat required. This can be obtained as follow:
Specific heat capacity (C) = 0.385 J/gºC
Change in temperature (ΔT) = 855 °C
Mass (M) = 22.8 g
Heat (Q) required =?
Q = MCΔT
Q = 22.8 × 0.385 × 855
Q = 7505.19 J
Thus, 7505.19 J of heat energy is required.
Doc. No.
QMS
Rev. Date
1. In the reaction
P
> M + N
a) The reactants are:
b) The products are:
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
20. What is an irreversible change?
Answer:
A change is called irreversible if it cannot be changed back again. For example you cannot change a cake back into its ingredients again. Irreversible changes are permanent.
Explanation:
Hope this helps!! :))
Having enough folic acid in your system by the early weeks of pregnancy is critical to prevent spina bifida.
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.
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
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!
In this lab, you will be making solutions of potassium permanganate (KMnO4), which has a formula weight of 158.04 g/mole. Remember to show your calculations and include tne Correct unnits in your answers
a) How many grams of KMnO4 would you need to make 1 L of a 2M solution?
b) How many grams of KMnO4 would you need to make 350 mL of a 0.75 M solution?
c) How many grams of KMnO4 would you need to make 80 mL of a 0.01 M solution?
Answer:
A. Mass of KMnO₄ = 316.08 g
B. Mass of KMnO₄ = 41.49 g
C. Mass of KMnO₄ = 0.13 g.
Explanation:
A. Determination of the mass of KMnO₄
We'll begin by determining the number of mole of KMnO₄ in the solution. This can be obtained as follow:
Volume = 1 L
Molarity = 2 M
Mole of KMnO₄ =?
Mole = Molarity × Volume
Mole of KMnO₄ = 2 × 1
Mole of KMnO₄ = 2 moles
Finally, we shall determine the mass of KMnO₄. This can be obtained as follow:
Mole of KMnO₄ = 2 moles
Molar mass of KMnO₄ = 158.04 g/mole
Mass of KMnO₄ =?
Mass = mole × molar mass
Mass of KMnO₄ = 2 × 158.04
Mass of KMnO₄ = 316.08 g
B. Determination of the mass of KMnO₄
We'll begin by determining the number of mole of KMnO₄ in the solution. This can be obtained as follow:
Volume = 350 mL = 350/1000 = 0.35 L
Molarity = 0.75 M
Mole of KMnO₄ =?
Mole = Molarity × Volume
Mole of KMnO₄ = 0.75 × 0.35
Mole of KMnO₄ = 0.2625 mole
Finally, we shall determine the mass of KMnO₄. This can be obtained as follow:
Mole of KMnO₄ = 0.2625 mole
Molar mass of KMnO₄ = 158.04 g/mole
Mass of KMnO₄ =?
Mass = mole × molar mass
Mass of KMnO₄ = 0.2625 × 158.04
Mass of KMnO₄ = 41.49 g
C. Determination of the mass of KMnO₄
We'll begin by determining the number of mole of KMnO₄ in the solution. This can be obtained as follow:
Volume = 80 mL = 80/1000 = 0.08 L
Molarity = 0.01 M
Mole of KMnO₄ =?
Mole = Molarity × Volume
Mole of KMnO₄ = 0.01 × 0.08
Mole of KMnO₄ = 0.0008 mole
Finally, we shall determine the mass of KMnO₄. This can be obtained as follow:
Mole of KMnO₄ = 0.0008 mole
Molar mass of KMnO₄ = 158.04 g/mole
Mass of KMnO₄ =?
Mass = mole × molar mass
Mass of KMnO₄ = 0.0008 × 158.04
Mass of KMnO₄ = 0.13 g