Answer:
The heat of reaction is the energy that is released or absorbed when chemicals are transformed in a chemical reaction. It describes the change of the energy content when reactants are converted into products.
Explanation:
Yeah, that would confuse me a bit but then you read it and then you will get that answer above! Have a great rest of your day!
Which substance can be identified as a homogeneous mixture?
chocolate milk
pepperoni pizza
chocolate chip cookie
peanut butter sandwich
Answer:
A) Chocolate Milk
Explanation:
A homogeneous mixture is one that is made of one substance. Technically, none of these are, but chocolate milk would be the closest. Pizza has cheese, pepperoni, and crust. Chocolate chip cookies have chips and the cookie. Peanut butter sandwiches have peanut butter and bread. Therefore, chocolate milk is right, as it has no other parts.
How many grams of water can be heated from 15.0 oC to 55oC using 4250.0 J.
Answer:
25.42 grams
Explanation:
The specific heat of water is 4.18 J/g •°C, so that means that it takes 4.18 joules of energy to raise one gram of water 1 °C.
Change in temp = 55 - 15 = 40°C
So we can calculate how much energy it would take to raise the temp of one gram of water by one degree using the following
(4.18 J/g•°C) * (40°C) * (1 gram) = 167.2 J
So if it takes 167.2 J of energy to raise on gram of water 40°C, we now we can calculate the amount of grams of water that can heated with 4250 J of energy
(4250 J) ÷ (167.2 J) = 25.42 grams of water can be heated from 15°C to 55°C
Why are fossil fuels considered nonrenewable resources?
Answer:
They are considered nonrenewable because they are prehistoric animals that has been extinct therefore can't be renew.
Use the scenario to answer the following question. A group of students working in a chemistry lab are planning a procedure to neutralize 10.0mL of 5.0 M hydrochloric acid (strong acid) with 5.0 M potassium hydroxide (strong base). In their procedure they plan on adding an equal volume of the base to the acid. What would be the expected outcome of carrying out this step as planned?
a- The resulting pH will be less than 7 because potassium hydroxide is less concentrated than the hydrochloric acid.
b- The resulting pH will not be able to be determined because the concentrations of the acid and base are not the same.
c- The resulting pH will be greater than 7 because potassium hydroxide is less concentrated than the hydrochloric acid.
d- The resulting pH will be equal to 7 because a strong base will neutralize a strong acid.
Answer:
d- The resulting pH will be equal to 7 because a strong base will neutralize a strong acid.
Explanation:
The reaction between potassium hydroxide and hydrochloric acid of equal volume and equal concentration yields a solution of pH 7 at equivalence point. We must note that KOH is a strong base while HCl is a strong acid. This fact influences the pH of the system at equivalence point.
Owing to the fact that the acid is exactly neutralized by the base; at the equivalence point of such titration, it is expected that hydrogen ions(H+) and hydroxide ions (OH-) must have reacted to form water, this leads to a final pH of 7.
Write the balanced half-reaction that occurs at the anode in a lead-acid (storage) battery during discharge. Phases are optional. anode half-reaction: Write the balanced half-reaction that occurs at the cathode in a lead-acid (storage) battery during discharge. Phases are optional. cathode half-reaction: Write the balanced overall cell reaction that occurs in the lead-acid (storage) battery during discharge. Phases are optional. overall cell reaction:
Answer: Anode: [tex]Pb+SO_4^{2-}\rightarrow PbSO_4+2e^-[/tex]
Cathode: [tex]PbO_2+4H^++SO_4^{2-}+2e^-\rightarrow PbSO_4+2H_2O[/tex]
Overall cell reaction : [tex]Pb+2SO_4^{2-}+PbO_2+4H^+\rightarrow 2PbSO_4+2H_2O[/tex]
Explanation:
Lead storage battery is a secondary cell used in automobiles and invertors. The anode is made up of lead and undergoes oxidation during discharging and cathode is made up of lead oxide and acts as cathode during discharging. The electrolyte used is dilute .
Lead storage battery acts as electrochemical cell while discharging.
Discharging reaction for Anode:
Discharging reaction for Cathode: [tex]PbO_2+4H^++SO_4^{2-}+2e^-\rightarrow PbSO_4+2H_2O[/tex]
Overall cell reaction : [tex]Pb+2SO_4^{2-}+PbO_2+4H^+\rightarrow 2PbSO_4+2H_2O[/tex]
A lead storage battery is an energy storage device. At the anode lead and sulfate ion reacts to produce Lead(II) sulfate and release two electrons.
What are anode and cathode?In secondary cells or the recharge-discharge cells during recharge, the positive electrode is the anode, while during discharge cathode is the positive electrode.
The anode (lead) of the cell undergoes an oxidation reaction during the discharge, whereas the lead oxide or the cathode undergoes reduction.
The discharging reaction at the anode of the cell is given as,
[tex]\rm Pb + SO_{4}^{2-} \rightarrow PbSO_{4} + 2e^{-}[/tex]
The discharging reaction at the cathode of the cell is given as,
[tex]\rm PbO_{2} + 4H^{+} + SO_{4}^{2-} + 2 e^{-} \rightarrow PbSO_{4} + 2H_{2}O[/tex]
The overall cell reaction is given as,
[tex]\rm Pb + 2SO_{4}^{2-} + PbO_{2} + 4H^{+} \rightarrow 2PbSO_{4} + 2H_{2}O[/tex]
Therefore, the gain and loss of electrons are represented at the cathode and the anode of the cell.
Learn more about discharge battery here:
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A solution is prepared by mixing 2.50g of CaCl2 with 50.0g H2O, what is the mass percent of CaCl2?
A. 3.76%
B. 4.76%
C. 5.76%
D. 6.76%
- Standard state refers to
a) 1 atm and 25°C
b) 1 atm and 100°C
c) 1 atm and gaseous reactants
d) None of these
Answer: The standard state refers to 1 atm and [tex]25^{o}C[/tex].
Explanation:
It is known that a chemical/substance can either be present in a solid, liquid or gaseous state.
So, when the phase of a substance like solid, liquid or gas is present at 1 atmosphere pressure and at a temperature of [tex]25^{o}C[/tex] then it known as standard state of substance.
Thus, we can conclude that standard state refers to 1 atm and [tex]25^{o}C[/tex].
How much ammonia would it take to neutralize 5ml of apple cider and 5ml of white vinegar if the ammonia had a molarity of 0.25?
Answer:
[tex]m_{NH_3}=0.0213gNH_3[/tex]
Explanation:
Hello there!
In this case, since it is known that the reaction between ammonia and acetic acid is:
[tex]CH_3COOH+NH_3\rightarrow CH_3COONH_4[/tex]
It is possible for us to realize that the mole ratio of acetic acid (vinegar) to ammonia is 1:1, that is why we can relate the concentrations as follows:
[tex]M_{acid}V_{acid}=M_{base}V_{base}\\\\[/tex]
In such a way, by knowing that the volume of these two are the same, we infer that their concentrations is also de same; and therefore, the mass of ammonia is calculated as:
[tex]m_{NH_3}=0.005L*0.25\frac{molNH_3}{L}*\frac{17.04gNH_3}{1molNH_3}\\\\m_{NH_3}=0.0213gNH_3[/tex]
Regards!
What is the name of Na
For each event stated below, indicate how the concentration of each species in the chemical equation will then change to reach equilibrium.
2CO(g) + O2(g) ⇌ 2CO2(g)
a. increasing the concentration of CO
b. decreasing the amount of O2
c. decreasing the the volume of the system
Answer:
See Explanation
Explanation:
When a constraint such as a change in temperature, concentration or pressure is imposed on a reaction system in equilibrium, the system will readjust itself in such a way as to annul the constraint. This readjustment occurs when the equilibrium position shifts towards the left or right in order to annul the constraint.
a. increasing the concentration of CO: When the concentration of CO is increased, the equilibrium position shifts to the right in order to annul the constraint. This means that more CO2 is produced in the system while the concentration of CO and O2 are decreased until equilibrium is reestablished.
b. decreasing the amount of O2: When the amount of O2 is decreased, the equilibrium position will shift to the left and more CO and O2 are produced while the concentration of CO2 decreases until equilibrium is reestablished.
c. decreasing the the volume of the system: When the volume of the system is decreased, the equilibrium position shifts towards the right hand side where there is less total volume. Hence the concentration of CO and O2 decreases while the concentration of CO2 increases.
A scientist wants to investigate several problems. In which of the following situations is using a simulation LEAST suitable for solving a problem?
a. When a scientific study requires performing a large number of trials that need to be conducted very quickly
b. When the solution to the problem requires real-world data inputs that are continually measured at regular intervals.
c. When performing an experiment that would be too costly or dangerous to conduct in the real world
d. When it is considered acceptable to make simplifying assumptions when modeling a real-world object or phenomenon
Answer:
A
Explanation:
got from another website
The simulation which is least suitable to scientists for solving a problem is when performing an experiment that would be too costly or dangerous to conduct in the real world.
What is scientific approach?Scientific approach is an empirical method of acquiring knowledge and result. This method involved the careful observation of the problem, applying skepticism about the problem and giving cognitive assumptions also.
If a scientist wants to investigate several problems, then they will perform a large no. of trials at regular intervals to get the required result. But if performing of any experiment is dangerous to conduct in the real world then scientists will ignore to solve that problem.
Hence, option (C) is correct.
To know more about scientific approach, visit the below ink:
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A gas has a volume of 6.00 liters at a temperature of 300 K and a pressure of 1.00 atm what is the volume of the gas in liters at a temperature of 600 K and a pressure of 3.00 atm
Answer:
V₂ = 4.00 L
Explanation:
Given that:
Volume (v1) = 6.00 L
Temperature (T1) = 300 K
Pressure (P1) = 1.00 atm
VOlume (V2) = unknown???
Temperature (T2) = 600 K
Pressure (P2) = 3.00 atm
Using combined gas law equation:
[tex]\dfrac{P_1V_1}{T_1}= \dfrac{P_2V_2}{T_2}[/tex]
[tex]\dfrac{1 \times 6}{300} = \dfrac{3 \times V_2}{600}[/tex]
[tex]\dfrac{1}{50} = \dfrac{1 \times V_2}{200}[/tex]
200 = 50V₂
V₂ = 200/50
V₂ = 4.00 L
Can someone give me an example of balancing equations with a solution that is simple?
Explanation:
[tex]H _{2}O _{2(aq)} →H _{2}O _{(l)} + O _{2}(g) \\ solution : 2 \: and\: 2[/tex]
Can someone please help me with this question.
Answer:
A-Sphalerite + Dioxygen+Zinc Oxide+Sulfur Trioxide
B-Sodium+Magnesium+Sodium iodide
Explanation:
Heyyy love good luck i may be wrong on letter B so if it is thats my bad but A should be correct :)
Phosphorus (P4) and hydrogen gas can combine to form phosphine (PH3), a toxic gas with the odor of rotting fish. Complete and balance the equation for this chemical reaction.
Answer:
P₄ + 6 H₂ ⇒ 4 PH₃
Explanation:
Let's consider the unbalanced reaction that takes place when phosphorus reacts with hydrogen to form phosphine. This is a synthesis reaction.
P₄ + H₂ ⇒ PH₃
We will balance this reaction using the trial and error method. First, we will balance P atoms by multiplying PH₃ by 4.
P₄ + H₂ ⇒ 4 PH₃
Finally, we get the balanced equation by multiplying H₂ by 6.
P₄ + 6 H₂ ⇒ 4 PH₃
A sample of air was collected on a day when the total atmosphere pressure was
592 mmHg. The sample contained only oxygen and nitrogen gas. If the oxygen in the sample had a pressure of 261 mmHg, how much pressure did the nitrogen
have? NOTE: You must show your calculation on the attached scratch paper,
including which of the Gas Law formulas you used. *
A. 853 mm Hg
B. 0.206 mm Hg
C. 4.76 mm Hg
D. 331 mm Hg
(Please show your work)
Answer:
1. The gas law used: Dalton's law of partial pressure.
2. Pressure of nitrogen = 331 mmHg
Explanation:
From the question given above, the following data were obtained:
Total pressure (Pₜ) = 592 mmHg
Pressure of Oxygen (Pₒ) = 261 mmHg
Pressure of nitrogen (Pₙ) =?
The pressure of nitrogen in the sample can be obtained by using the Dalton's law of partial pressure. This is illustrated below:
Pₜ = Pₒ + Pₙ
592 = 261 + Pₙ
Collect like terms
592 – 261 = Pₙ
331 = Pₙ
Pₙ = 331 mmHg
Therefore, the pressure of nitrogen in the sample is 331 mmHg
In this experiment, you will need to prepare 250.0 mL of 0.100 M KCl(aq) solution. Determine the mass in grams of potassium chloride required to prepare this solution. Type your numerical answer (no units) in the box below. Even though the number of significant figures is limited to three by the inputs, please report your answer to four significant figures.
Answer: The mass in grams of potassium chloride required to prepare this solution is 1.862 grams
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
[tex]Molarity=\frac{n\times 1000}{V_s}[/tex]
where,
n = moles of solute
[tex]V_s[/tex] = volume of solution in ml
moles of [tex]KCl[/tex] = [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{xg}{74.5g/mol}[/tex]
Now put all the given values in the formula of molality, we get
[tex]0.100=\frac{x\times 1000}{74.5g/mol\times 250.0ml}[/tex]
[tex]x=1.862g[/tex]
Therefore, the mass in grams of potassium chloride required to prepare this solution is 1.862 grams
Qué uso le darías en la vida diaria ayuda
Answer:
ako po kailangan ko po nga ayuda
Explanation:
thanks for the points ❤️
8. Sulfur has a first ionization energy of 1000 kJ/mol. Photons of what frequency are required to ionize one mole of Sulfur?
Answer:
the frequency of photons [tex]v = 1.509\times10^{39}Hz[/tex]
Explanation:
Given: first ionization energy of 1000 kJ/mol.
No. of moles of sulfur = 1 mole
[tex]\Delta E_1 = 1000KJ/mol[/tex]
We know that plank's constant
[tex]h = 6.626\times10^{-34} Js[/tex]
Let the frequency of photons be ν
Also we know that ΔE = hν
this implies ν = ΔE/h
[tex]= \frac{10^6J}{6.626\times10^{-34} Js}[/tex]
[tex]v = 1.509\times10^{39}Hz[/tex]
Hence, the frequency of photons [tex]v = 1.509\times10^{39}Hz[/tex]
balance the equation P + O2 → P4O10
For many purposes we can treat butane as an ideal gas at temperatures above its boiling point of . Suppose the pressure on a sample of butane gas at is cut in half. Is it possible to change the temperature of the butane at the same time such that the volume of the gas doesn't change? yes no If you answered yes, calculate the new temperature of the gas. Round your answer to the nearest °C.
Answer:
A. Yes
B. The new temperature of the gas is -116 °C
Note: The question is incomplete. The complete question is given below :
For many purposes we can treat butane C H10) as an ideal gas at temperatures above its boiling point of - 1. °C. Suppose the pressure on a 500 mL sample of butane gas at 41.0°C is cut in half. Iyes Is it possible to change the temperature of the butane at the same time such that the volume of the gas doesn't change? yes no If you answered yes, calculate the new temperature of the gas. Round your answer to the nearest °C.
Explanation:
A. According to the pressure law of gases,for a fixed mass of gas the pressure of a gas is directly proportional to its Kelvin temperature once the volume is kept constant. This means that a change in temperature can bring about a change in pressurein a gas at constant volume.
B. From the pressure law of gasese: P1/T1 = P2/T2
Where initial pressure = P1, final pressure = P2
Initial temperature = T1, final temperature = T2
For the butane gas;
P1 = P
P2 = P/2
T1 = 41°C = (273 + 41 ) K = 314 K
T2 = ?
From the equation, T2 = T1 × P2 / P1
T2 = 314 × P/2 /P
T2 = 157 K
T2 = (157 - 273) °C = -116 °C
Therefore, the new temperature of the gas is -116 °C
PLZ ANSWER QUICK I AM IN TIMER HELP WILL GIVE BRAINLIEST
Which is greater, the moon's period of rotation or its period of revolution?
They are equal.
the moon's revolution period around Earth
Neither are known.
the moon's rotational period
Answer:
B
Explanation:
_____ the irregular break of a mineral.
a. Habit
b. arrangement
c. cleavage
d. Fracture.
Answer:
D Fracture
Explanation:
jus took the test
For the following reaction conditions select the correct statement regarding the reaction below.
OH Cl OTs OTs N TsCl W X Y Z N
a. W is the correct product.
b. X is the correct product.
c. Y is the correct product.
d. Z is the correct product since pyridine acts as a nucleophile.
e. Both X and Y are both formed in this reaction as a racemic mixture
Answer:
B
Explanation:
The appropriate diagram of the question is shown in the first image attached below.
From the diagram, we see the reaction of Cyclopentanol taking place under Tscl pyridine. We are to show the reaction mechanism and determine from the options, which appropriate product fits in.
So, from the reaction, the hydroxyl substituent reacts with Tscl where cl is being lost. This process is followed by an attack of N substituent on the pyridine with the Hydrogen atom and cleaves off for the structure to form a stable structure. The stereochemistry of the compound remains unchanged and it maintains its stick formula.
Thus, X is the appropriate and the correct product.
8. Calculate (H^+), (OH^-), pOH and the pH for a 0.00024 M solution of calcium hydroxide. Must show work!
Answer:
1. [H⁺] = 2.0×10¯¹¹ M
2. [OH¯] = 4.8×10¯⁴ M
3. pOH = 3.3
4. pH = 10.7
Explanation:
From the question given above, the following data were obtained obtained:
Molarity of Ca(OH)₂ = 0.00024 M
We'll begin by calculating the concentration of the hydroxide ion [OH¯]. This can be obtained as follow:
Ca(OH)₂ (aq) —> Ca²⁺ + 2OH¯
From the balanced equation above,
1 mole of Ca(OH)₂ produced 2 moles of OH¯.
Therefore, 0.00024 M Ca(OH)₂ will produce = 2 × 0.00024 = 4.8×10¯⁴ M OH¯
Thus, the concentration of the hydroxide ion [OH¯] is 4.8×10¯⁴ M
Next, we shall determine the pOH of the solution. This can be obtained as follow:
Concentration of the hydroxide ion [OH¯] = 4.8×10¯⁴ M
pOH =?
pOH = –Log [OH¯]
pOH = –Log 4.8×10¯⁴
pOH = 3.3
Next, we shall determine the pH of the solution. This can be obtained as follow:
pOH = 3.3
pH =?
pH + pOH = 14
pH + 3.3 = 14
Collect like terms
pH = 14 – 3.3
pH = 10.7
Finally, we shall determine the concentration of hydrogen ion [H⁺]. This can be obtained as follow:
pH = 10.7
Concentration of hydrogen ion [H⁺] =?
pH = –Log [H⁺]
10.7 = –Log [H⁺]
Divide both side by –1
–10.7 = Log [H⁺]
Take the antilog of –10.7
[H⁺] = Antilog (–10.7)
[H⁺] = 2.0×10¯¹¹ M
SUMMARY:
1. [H⁺] = 2.0×10¯¹¹ M
2. [OH¯] = 4.8×10¯⁴ M
3. pOH = 3.3
4. pH = 10.7
bakit mahalaga ang ilaw trapiko?
grade 3
Explanation:
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maybe umm think so pick think so
Suppose that you must go into court and testify as to the level of X in the river water. Your lawyer is concerned that your analytical results are lower than they should be because you cannot extract with benzene (distribution Ratio K=4) all of X from your samples. Assume the concentration of X in the 1.00 L river water sample is 1.06 x 10-4 M.
a. How many extracts would be required to remove all but 1000 molecules of X from the sample with repeated 10.00 mL portions of extract?
b. How many extractions are required for a 99.99% chance of extraction of the last molecule remaining (0.01% chance of a single molecule left behind)
Answer:
The appropriate solution is:
(a) n ≈ 900
(b) n ≈ 1165
Explanation:
According to the question,
(a)
The final number of molecules throughout water will be:
= [tex](\frac{1000}{1000}\times 4\times 10 )^n[/tex]
where, n = number of extractions
Now,
The initial number of molecules will be:
= [tex]1.06\times 10^{-4}\times 6.023\times 10^{23}[/tex]
= [tex]6.387\times 10^{19}[/tex]
Final number of molecule,
⇒ [tex]1.566\times 10^{-16}=(\frac{1000}{1040} )^n[/tex]
[tex]n \approx 900[/tex]
(b)
Final molecules of X = left (0.01%)
hence,
⇒ [tex]initial = 6.384\times 10^{19}[/tex]
[tex]\frac{1}{6.384\times 10^{19}} =(\frac{1000}{1040} )^2[/tex]
[tex]n \approx 1165[/tex]
How many atoms are there in 24 moles of Fe?
Answer: There are [tex]145 \times 10^{23}[/tex] atoms in 24 moles of Fe.
Explanation:
According to the mole concept, 1 mole of a substance contains [tex]6.022 \times 10^{23}[/tex] atoms.
Therefore, atoms present in 24 moles of Fe are calculated as follows.
[tex]24 mol \times 6.022 \times 10^{23} atoms/mol\\= 144.52 \times 10^{23} atoms\\or, 145 \times 10^{23} atoms[/tex]
Thus, we can conclude that there are [tex]145 \times 10^{23}[/tex] atoms in 24 moles of Fe.
Metal plating is done by passing current through a metal solution. For example, an item can become gold plated by attaching the item to a power source and submerging it into a Au3 solution. The item itself serves as the cathode, at which the Au3 ions are reduced to Au(s). A piece of solid gold is used as the a node and is also connected to the power source, thus completing the circuit.
Required:
What mass of gold is produced when 15.0A of current are passed through a gold solution for 15.0min ?
Answer:
9.18g
Explanation:
Step 1: Write the reduction half-reaction
Au³⁺(aq) + 3 e⁻ ⇒ Au(s)
Step 2: Calculate the mass of gold is produced when 15.0A of current are passed through a gold solution for 15.0min
We will use the following relationships:
1 min = 60 s1 A = 1 C/s1 mole of electrons has a charge of 96486 C (Faraday's constant).1 mole of Au is produced when 3 moles of electrons circulate.The molar mass of Au is 196.97 g/mol.The mass of gold produced is:
[tex]15.0 min \times \frac{60s}{1 min} \times \frac{15.0C}{1s} \times \frac{1 mol e^{-} }{96486C} \times \frac{1molAu}{3 mol e^{-} } \times \frac{196.97gAu}{1molAu} = 9.18gAu[/tex]