Matthew added a sample of sodium chloride to water and
found the poH to be 2,55. What is the pH of the salt solution?
pH
Answer:
11.45
Explanation:
The ph is just 14-pOH so
14-2.55=ph=11.45
C(s) + O2(g) → CO2(g) ΔHº = -94.6 kJ
H2(g) + \scriptsize \frac{1}{2}O2(g) → H2O(l) ΔHº = -286.0 kJ
2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O (l) ΔHº = -2598.8 kJ
calculate the value of ΔHº for the final reaction:
2C(s) + H2(g) → C2H2(g) ΔHº = kJ
The value of enthalpy(ΔHº) for the final reaction (2C(s) + H₂(g) → C₂H₂(g) ) is -1932.8KJ.
Enthalpy change: what is it?A system's enthalpy is its heat capacity. A reaction's enthalpy change is roughly equivalent to how much energy is lost or gained throughout the reaction. If the enthalpy of the system decreases over the reaction, the reaction is preferred.
C(s) + O₂(g) → CO₂(g) ΔHº = -94.6 kJ --- (1)
H₂(g) + O₂(g) → H₂O(l) ΔHº = -286.0 kJ ---(2)
2C₂H₂(g) + 5O₂(g) → 4CO₂(g) + 2H₂O (l) ΔHº = -2598.8 kJ ---(3)
The value of ΔHº for the final reaction,
2C(s) + H₂(g) → C₂H₂(g)
ΔH₄° = 2× ΔH₂º + ΔH₃º - ΔH₁º
ΔH₄° = 2× -286.0 + ( -2598.8) - (- 94.6)
ΔH₄° = 2× -286.0 -2598.8 + 94.6
ΔH₄° = 666 - 2598.8
ΔH₄° = -1932.8KJ.
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g h g jg jh gj h g jhg u iga ff f. f. f f f
Which of these is an example of a physical property?
A. Iron combines with oxygen to rust.
B. Potassium reacts in water to form a base.
C. Sodium metal is soft and malleable.
D. Sodium ignites when placed in water.
20. A compound's empirical formula is C,H,O. If the molecular mass of the compound is
162.2g, what is the molecular formula?
NO LINKS PLEASE THIRD TIME IM POSTING THIS ITS DUE IN 8min
Answer:
Just use a text book.. So that you get the concept
What is the importance of a chemical symbol?
Answer:
Chemical symbols are used to standardize the 'language of chemistry' and to identify elements and atoms in a chemical formula easily. Chemical symbols consist of one or two letters, most often derived from the name of the element.
Explanation:
Answer:
Explanation:
A chemical symbol is a notation of one or two letters representing a chemical element. Its used to identify elements and atoms in a chemical formula easily. Chemical symbols consist of one or two letters, most often derived from the name of the element.
What is the molarity of a solution containing 2 moles of sodium hydroxide (NaOH) dissolved in 4.0 L of solution?
Answer:
0.5M
Explanation:
Molarity = Mols/ Liters
so 2/4
0.5 M
help me please| (• ◡•)|
Answer:
1 = rusting of ice
2 = will change the properties of substance
3= gas to liquid
4= melting point
5= it moves from a warmer region to colder region
PLZ HELP ASAP
Approximately how many grams of potassium chloride(KCI) are required to prepare 600. mL of a 2.50 M solution ?
A) 103 g
B) 112 g
D) 125 g
(B)
Explanation:
2.50 M KCl = (2.50 mol KCl/L)(0.600 L) = 1.50 mol KCl
molar mass of KCl = 74.5513 g KCl/mol
1.50 mol KCl × (74.5513 g KCl/mol) = 112 g KCl
Which molecules do your cells get from food?
(Select two answers)
A) Amino Acid
B) Glucose
C) Oxygen
D) Carbon Dioxide
Answer:
b
Explanation:
mark me brainliest pls
Answer:
b
Explanation:
bc
5. True or False: If one thing in a food web is affected, it will only probably affect the organism that directly relies on it for energy. *
1 point
A. True
B. False
A solution is made of 12 g NaCl and 70.0 g water. What is the % NaCl?
PLEASE HELP! 80 POINTS
Create a VESPR drawing for
NH3
CH20
N3
SO2CI2
BrF5
Answer:
hope it helps you
can be generally defined as a change in position OA. Mass OB. Force OC. Volume OD. Motion Reset
Answer:
Not sure were to start....
Explanation:
Answer: motion
Explanation: hope this helps you
Balancing chemical reactions. What is it and examples
Answer: A balanced chemical reaction is A balanced chemical equation where the number of atoms of each type in the response is the same on both reactants and product sides.
Explanation: Burning, and cooking are 2 examples.
What is the percent composition of a copper chloride compound if a 269 g sample contains 127 g of copper and 142 grams of chlorine.
Answer:
Explanation:
The whole sample is 269
%copper = 127/269 * 100 = 47.2%
%chlorine = 142/269 * 100 = 52.8%
That's all you are asking. Is there more?
An experiment requires 65.00 g of sodium chloride. Sodium chloride is available at a price of $179.0 per 5.000 kg sodium chloride. What is the cost of the sodium chloride in the experiment (reported to the hundredths place because we're working with dollars)?
Answer: on
Explanation:5
The price of sodium chloride per 5 kg is 179 dollars. The experiment requires 65 g of NaCl. The price of65 g or 0.065 kg is 2.3 dollars.
What is sodium chloride?Sodium chloride is an ionic compound formed by the combination of sodium metal and chlorine atom. Sodium metal has extra one electron in its valance shell and chlorine needs one more electron into its valence shell. Hence sodium donates its valence electron to chlorine forming NaCl.
NaCl is used as the table salt in food. It is a very important compound in our daily diet. Similarly NaCl is industrially important for many reaction especially in electrochemical processes.
It is given that, the price of 5 kg of NaCl = $179
required mass of NaCl = 65 g = 0.065 Kg
then , price of 0.065 kg = (0.065 × 179 /5) = $2.31
Therefore, the cost of NaCl in the experiment is 2.31 dollars.
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A sample of gas occupies 200 L at 780 mm Hg and 280 K. What is the new volume, in liters, of the gas at 810 mm Hg and 300 K?
Given :
A sample of gas occupies 200 L at 780 mm Hg and 280 K.
To Find :
The new volume, in liters, of the gas at 810 mm Hg and 300 K.
Solution :
We know, by ideal gas equation :
[tex]PV = nRT[/tex]
Since, every thing is constant except [tex]nR[/tex] .
So,
[tex]\dfrac{P_1V_1}{T_1} = \dfrac{P_2V_2}{T_2}[/tex]
Putting all given values we get :
[tex]V_2 = \dfrac{T_2}{T_1}\times \dfrac{P_1}{P_2}\times V_1\\\\V_2 = \dfrac{300}{280}\times \dfrac{780}{810}\times 200\ L\\\\V_2 = 206.35 \ L[/tex]
Therefore, the new volume is 206.35 L.
Sometimes Combination reaction takes place sometimes decomposition and sometime replacement.. Can someone say me the conditions required for it?
Do not tell the defination of decomposition, replacement and of combination.. During reaction sometimes gas is formed sometimes not..
Can Some one explain it in a well manner.. Do not give Undesirable answer:
Whenever any substance goes under chemical change so any of the reaction will happen either both or multiple compounds will combine to produce combination reaction either one compound will decompose itself into 2 or more compounds or elements and last one is replacement reaction the either reaction is not even going to combination nor decomposition, So when a reaction like that happens it must replacement reaction.
Now the question is what's the condition required for it, so basically a chemical reaction when takes place it depends upon several factor on the basis of which we conclude products. The factors are Temperature,catalyst,reagents, either what is the mechanism of reaction, stability of reactants and stability of products and alot more.
During reaction sometimes gas forms and sometimes not yea and well that also depends on the chemical reactivity and stability of product sometimes product found itself most stable releasing the gas evolving so it's been done itself and sometimes we add catalyst and adjust the reaction to extract that gas and get desirable product manually.
I wrote all i know if sorry if this is not what you're looking for :(
A 0.982-g sample of an unknown gas exerts a pressure of 700 mm Hg in a 450-cm3 container at 23oC. Calculate the molar mass of this gas. [1cm3 = 1mL; 1000mL = 1L]
Answer:
57.4 g/mol
Explanation:
Step 1: Convert 450 cm³ to L
We will use the conversion factors 1 cm³ = 1 mL and 1000 mL = 1 L.
450 cm³ × 1 mL/1 cm³ × 1 L/1 mL = 0.450 L
Step 2: Convert 23 °C to Kelvin
We will use the following expression.
K = °C + 273.15 = 23 + 273.15 = 296 K
Step 3: Calculate the number of moles of the gas
We will use the ideal gas equation.
P × V = n × R × T
n = P × V / R × T
n = 700 mmHg × 0.450 L / (62.4 mmHg.L/mol.K) × 296 K = 0.0171 mol
Step 4: Calculate the molar mass of the gas
0.982 g of the gas correspond to 0.0171 moles.
M = 0.982 g/0.0171 mol = 57.4 g/mol
In "The Philosophy of the Manufacturers" by Andrew Ure, the author compares a factory worker to a handmade
worker. The author leads the reader to the idea that the factory worker is better off. Choose evidence (a quote
from the text) to support this idea.
a. Certainly no muscular fatigue to sustain, while it procures for him good, unfailing wages, besides a
healthy workshop gratis.
b. The lot of mankind, have been too little dwelt upon; while, on the other har, it has been accused of
lending itself to the rich capitalists as an instrument for harassing the poor.
c. The principle of the factory system then is, to substitute mechanical science for hand skill, and the
partition of a process into its essential constituents.
"Certainly no muscular fatigue to sustain, while it procures for him good, unfailing wages, besides a healthy workshop gratis."
What idea does the quote supports?The concept that factory workers have it better than handcrafted workers is supported by this textual quotation since it implies that factory work is less physically taxing and offers better pay and working conditions.The author is suggesting that factory worker is in better position than hand worker.This is beneficial for the worker, as it means they can work for longer periods of time without experiencing the same level of exhaustion.Finally, the quote states that a factory provides a "healthy workshop gratis" which means that the factory provides a healthy and clean working environment for the worker without any additional costs. This is beneficial for the worker, as it means they can work in a safe and healthy environment, which is not always the case for hand workers.To know more about healthy workshop conditions quote, check out :
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You have three solutions of nickel complex ions, one is blue, one is violet, and one is green. Match the complex ion with the correct solution color.
A. [Ni(en)3]2+
B. [Ni(H2O)6]2+
C. [Ni(NH3)5]2+
Answer:
Explanation:
A. [Ni(en)₃]²⁺ --------- Violet
B. [Ni(H₂O)₆]⁺² -------Green
C. [Ni(NH₃)₅]⁺² ---------Blue .
Are weathering and erosion two different names for the same process? Explain why or why not.PLEASE HELP!
Answer:
While weathering and erosion are similar processes, they are not synonymous. Weathering involves the breakdown of rocks and minerals on Earth, whereas erosion involves the removal of soil and rock materials.
Can somebody answer these questions
I know it this one is easy I had the same one.
Which of the following is an electrolyte?
CH4OH
O Ca(NO3)2
O C12H22011
O CH3CH2OH
Answer:
B. Ca(NO3)2
Explanation:
edg 2022
Answer:
b
Explanation:
hydrates (1 question)
6) When 10.000 g of a hydrated compound are analyzed in the laboratory, the following analysis is obtained: 1.425 g of water, 5.462 g of lead, 1.266 g of carbon, 1.687 g of oxygen, and 0.160 of hydrogen. What are the name and formula of the compound?
The name and formula of the compound can be determined by analyzing the data given in the question. Based on the information provided, the compound contains lead, carbon, oxygen, and hydrogen. The molecular formula for the compound can be determined by adding up the number of atoms of each element present.
From the data given, the compound contains 1.266 g of carbon, which is equivalent to 1.266/12.01 = 0.105 mol of carbon atoms. It also contains 5.462 g of lead, which is equivalent to 5.462/207.2 = 0.026 mol of lead atoms. The compound also contains 1.687 g of oxygen, which is equivalent to 1.687/16.00 = 0.105 mol of oxygen atoms, and 0.160 g of hydrogen, which is equivalent to 0.160/1.01 = 0.158 mol of hydrogen atoms.
The molecular formula for the compound is therefore Pb(C2H2O2). However, it is also mentioned that the compound is hydrated, which means that it contains water. The 1.425 g of water present in the compound is equivalent to 1.425/18.02 = 0.079 mol of water molecules. The compound 1 likely Pb(C2H2O2)·xH2O, where x represents the number of water molecules present in the compound.
CAN SOMEONE HELP ME PLS I HAVE A FINAL TMMR WITH THESE
write the states of matter and balanced equations
- in the presence of heat gold (ll) acetate decomposes
- aluminum wire is added to a solution of nickel (ll) nitrate
- a solution of sodium phosphate is added to a solution of ammonium chromate
The states of matter and balanced equations are as follows:
Au(C₂H₃O₂)₂ (s) --> Au (s) + 2CO₂ (g) + 3H₂O (g)Al (s) + Ni(NO₃)₂ (aq) --> Al(NO₃)₃ (aq) + Ni (s)Na₃PO₄ (aq) + NH₄CrO₄ (aq) --> NaCrO₄ (aq) + NH₄PO₄ (aq)What is a balanced chemical reaction?Chemical bonds are broken and new bonds are formed during chemical reactions, but atoms in the reactants do not disappear and new atoms do not form products. Chemical reactions do not create or destroy atoms. The same atoms that were present in the reactants are present in the products—they are just rearranged in different configurations. must exist in
The subscript is part of the formula and should not be changed once the reactant and product formulas have been determined. The coefficients indicate the number of each substance involved in the reaction and can be changed to balance the equation.
In the presence of heat Gold (ll) acetate decomposes:
Au(C₂H₃O₂)₂ (s) --> Au (s) + 2CO₂ (g) + 3H₂O (g)
Aluminum wire is added to the solution of nickel (ll) nitrate:
Al (s) + Ni(NO₃)₂ (aq) --> Al(NO₃)₃ (aq) + Ni (s)
A solution of sodium phosphate is added to the solution of ammonium chromate:
Na₃PO₄ (aq) + NH₄CrO₄ (aq) --> NaCrO₄ (aq) + NH₄PO₄ (aq)
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why is carbon IV oxide and water removed before liquefication of air?
Answer:
Because when they unfreeze and are cooled they would block pipes of the air liquefaction plant and make the air colder, hope this helps!!
If the temperature of 85.0 g of copper changes from 28.0°C to 99.0°C, how much
heat was absorbed? The specific heat capacity of copper is 0.385 J/K:g. Write your
answer to 3 sig figs.
Answer:
2320 J
Explanation:
We'll begin by calculating the change in temperature of the copper. This can be obtained as follow:
Initial temperature (T₁) = 28.0 °C
Final temperature (T₂) = 99.0 °C
Change in temperature (ΔT) =?
ΔT = T₂ – T₁
ΔT = 99 – 28
ΔT = 71 °C
Finally, we shall determine the heat absorbed by the copper. This can be obtained as follow:
Mass of copper (M) = 85 g
Change in temperature (ΔT) = 71 °C
Specific heat capacity (C) = 0.385 J/K.g
Heat (Q) absorbed =?
Q = MCΔT
Q = 85 × 0.385 × 71
Q = 2320 J
Thus, the heat absorbed is 2320 J
Choose the correct statement. At a higher temperature……………..
1.Energies of particles increase
2.Rate of reaction increases
3.Particles collide more frequently
4.All correct
Answer:
4. All correct
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