The limestone used in building the Egyptian pyramids was used because it is _____________
O soft and sticky
O easily melted
O hard and brittle
Answer:
hard and brittle
hope this helps you ☺️☺️
good night take care sweet dream
What is the empirical formula for C6H12?
Answer:
The empirical formula of C6 H12,
3. Determine the enthalpy of formation for propane. 3C(s, gr) + 4H2(g) ---> C3H2(g) CzH3(g) AH = -2219.9 kJ C(s, gr) AH = -393.5 kJ H,(g) AH = -285.8 kJ a. -205.7 /mol b. -103.8 kJ/mol Å C. + 205.7 /mol d. + 103.8 /mol
Answer:
b I hope this is right good luck
Identify the term that matches each electrochemistry definition.
a. The electrode where reduction occurs ___________
b. An electrochemical cell powered by a spontaneous redox reaction ___________
c. The electrode where oxidation occurs__________
d. An electrochemical cell that takes in energy to carry out a nonspontaneous redox reaction ____________
e. A chemical equation showing either oxidation or reduction ___________
Answer: a. Cathode
b. Galvanic cell
c. Anode
d. Electrolytic cell
e. half reaction
Explanation:
Galvanic cell or Electrochemical cell is defined as a device which is used for the conversion of the chemical energy produced in a spontaneous redox reaction into the electrical energy.
Electrolytic cell is a device where electrical energy is used to drive a non spontaneous chemical reaction.
In the electrochemical cell, the oxidation occurs at an anode which is a negative electrode and the reduction occurs at the cathode which is a positive electrode. Thus the electrons are produced at anode and travel towards cathode.
The balanced two-half reactions will be:
Oxidation half reaction : [tex]M\rightarrow M^{n+}+ne^-[/tex]
Reduction half reaction : [tex]N^{n+}+ne^-\rightarrow N[/tex]
Thus the overall reaction will be: [tex]M+N^{n+}\rghtarrow M^{n+}+N[/tex]
If I have 7.0 x 10^24 formula units of magnesium chloride, how many grams of chlorine would I have?
Answer:
824 g
Explanation:
First we convert 7.0 x 10²⁴ formula units of magnesium chloride (MgCl₂) into moles, using Avogadro's number:
7.0 x 10²⁴ formula units ÷ 6.023x10²³ formula units/mol = 11.62 mol MgCl₂There are two Cl moles per MgCl₂ moles, meaning that we have (2 * 11.62) 23.24 moles of Cl
Finally we convert 23.24 moles of chlorine into grams, using chlorine's molar mass:
23.24 mol * 35.45 g/mol = 824 gWhat happens when particles collide in sound waves?
Answer:
When sound is created, the air particles vibrate and collide with each other, causing the vibrations to pass between air particles. The vibrating particles pass the sound through to a person's ear and vibrate the ear drum. Light travels much faster than sound through air.
Explanation:
if a lake has excess levels of phosphates and nirates in its water what will most likely result ?
Answer:
Eutrophication
Explanation:
Eutrophication results when there is excess levels of phosphates and nitrates in its water of lake.
When there is high level of nutrition level in the water body of lake, then the productivity of water plants increases thereby leading to algal boom and hence Eutrophication.
Write a scientific explanation that answers the following question: Is matter conserved during a
chemical reaction in both closed and open systems?
Claim:
Evidence:
Reasoning:
Answer:
Matter is conserved during all chemical reactions because matter cannot be created or destroyed.
Explanation:
The initial volume of a gas is 21 L and the final volume is 38.7 L. If the initial temperature was 261 K, what is the final temperature (in Kelvin)?
Answer:
480.9K
Explanation:
V1=21L
V2=38.7L
T1=261K
T2=?
Using Charles law,
V1/T1=V2/T2
Inputting the given values,
21/261=38.7/T2
T2=480.9K
5. Vilayanur Ramachandran belleves that in order to understand how our brains work, we need to look at brains that don't work as they should in order to see the differences
and effects that the disconnect of neurons can have on our memories, thoughts, and understanding.
True
O False
Answer:
true
Explanation:
What value is equivalent to 7.2 kilograms
Answer: 15.8732828773 pounds
Explanation:
Which property do all metals have?
А They are hard.
B They conduct electricity.
С They form acidic oxides.
D They react with water.
2
A student put 25.0 cm of dilute hydrochloric acid into a conical flask.
The student added 2.5g of solid sodium carbonate and measured the change in temperature of
the mixture.
Which apparatus does the student need to use to obtain the most accurate results?
A balance, measuring cylinder, thermometer
B balance, pipette, stopwatch
C balance, pipette, thermometer
D
burette, pipette, thermometer
Answer:
A balance, measuring cylinder, thermometer
Explanation:
In this experiment, three things are really required and they are;
A balance Measuring cylinderThermometerA balance is used to measure out the mass of 2.5g of solid sodium carbonate.
A measuring cylinder is used to measure out the 25.0 cm of dilute hydrochloric acid into a conical flask.
Lastly, a thermometer is used to monitor the change in temperature.
[tex]\huge \underbrace \mathfrak \red {Question: } [/tex]
❥How can an acid be diluted?
Explanation:
Acid can be diluted through the distillation process in which acid is reacted with distilled substance like distilled water.
Answer:
an acid be diluted by distillation process.
A 108.9 g sample of water absorbs 114.6 calories of heat. The specific heat capacity of water is 1 cal/(g·°C). By how much did the temperature of this sample change, in degrees Celsius?
Answer:
The temperature of this sample changes by 1.052 degrees Celsius
Explanation:
As we know
[tex]Q = mc\Delta T[/tex]
Where m is the mass of the substance
c is the specific heat of the substance
and [tex]\Delta T[/tex] is the change in temperature
Substituting the given values in above equation, we get -
[tex]114.6 = 108.9 * 1 * \Delta T\\\Delta T = 1.052[/tex]degree Celsius
The temperature of this sample changes by 1.052 degrees Celsius
does anyone know thisss???
A mixture of water and water vapor is present in a closed vessel at 20 degrees Celsius. the total pressure of the system is 755.0 mmHg. Partial pressure of water vapor at 20 degrees Celsius equals 17.5 mm Hg. What is the partial pressure of H2
Answer:
737.5 mmHg
Explanation:
Ptotal=PH2O+PH2
P is the pressure and since we have Ptotal and PH2O, we can solve for PH2
755=17.5+x
755-17.5=x
x=737.5
Predict the reactants of this chemical reaction. That is, fill in the left side of the chemical equation.
______ + Cacl2 → H2O
Answer: [tex]Ca(OH)_2+2HCl\rightarrow CaCl_2+2H_2O[/tex]
Explanation:
Neutralization is a chemical reaction where an acid reacts with a base to form salt and water.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side.
The balanced chemical equation will be:
[tex]Ca(OH)_2+2HCl\rightarrow CaCl_2+2H_2O[/tex]
Thus the reactants are calcium hydroxide [tex](Ca(OH)_2[/tex] and hydrochloric acid [tex](HCl)[/tex]
Which equation represents single replacement reaction? A) CH4 + 2 02 → CO2 + 2 H2O B) CaCO3 + CaO + CO2 C) 2 Na + 2 H2O → 2 NaOH + H2 D) LiOH + HCl → LiCl + H2O
Answer:
C) 2 Na + 2 H2O → 2 NaOH + H2.
Explanation:
Hello there!
In this case, according to the given chemical reactions, it is possible to firstly understand that a single displacement reaction is characterized by the presence of a single element as the first reactant and a compound as the second one, thus, yielding a compound as the first product and a single element as the second one.
In such a way, according to the given choices, it possible to note that C) 2 Na + 2 H2O → 2 NaOH + H2 is the only one with the aforementioned condition as the element at the reactants side is Na and at the products side is H2.
Best regards!
IM GIVING 100 POINTS FOR WHOEVER ANSWERS THIS PLS HELP determine which heat transfers below are due to the process of conduction. I) You walk barefoot on the hot street and it burns your toes. II) When you get into a car with hot black leather seats in the middle of the summer and your skin starts to get burned when you touch the seats. III) A flame heats the air inside a hot air balloon and the balloon rises. IV) A boy sits to the side of a campfire. He is 10 feet away, but still feels warm. Question 1 options: I & II III & IV I, II, & IV II, III, IV
Answer:
I and II
Explanation:
what is the difference between an acid and a base?
Answer:

A substance, mostly liquid that donates a proton or accepts an electron pair in reactions. An acid increases the concentration of H+ ions. A base is a substance that releases hydroxide (OH-) ions in aqueous solution, donates electrons and accepts protons.
[tex]{\underline{\underline{\bf{\red{\:\:Acid\:\:}}}}}[/tex]
Proton donor and electron pair acceptorIt can increase the concentration of H+ ion in aq. solution.pH value is <7Turn blue litmus paper into redAcid reacts with bases to form saltsAcid taste sour[tex]{\underline{\underline{\bf{\orange{\:\:Base\:\:}}}}}[/tex]
Proton acceptor and electron pair donorIt can increase the concentration of OH- ion in aq. solution.pH value is >7Turn red litmus paper into blueBases reacts with acids to form saltsBases taste soapyMatch each definition to the appropriate term.
Sum of the internal energy plus the product of the pressure and volume for a reaction
The extent of randomness in a system
The condition that a reaction takes place without outside help
Difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature
Solution in which no more solute can be dissolved in the solvent
Answer:
Enthalpy, Entropy, Spontaneity, Gibbs free energy, saturated solution
Explanation:
Enthalpy is defined as the heat released or the heat absorbed during the process at a constant pressure which is equal to the Enthalpy shift. Enthalpy is also called as heat content and it is the sum total of internal energy and the product of the volume and pressure of a system.
Entropy is defined as the measure of randomness of a system or the disorder of the system.
Spontaneity is defined as the condition of being spontaneous. It is the condition where a reaction takes place without any help from outside.
Gibbs free energy is defined as the energy that is used to quantify the maximum work done in a thermodynamic system at constant temperature and pressure. It is the also known as the Gibbs energy or function.
Saturated solution is defined as the solution where the maximum amount of the dissolved solute is present in the solvent. In case of a saturated solution, the extra solute does not dissolve. In order words, it is a solution where no more solute can dissolved in solvent.
The sum of the internal energy plus the product of the pressure and volume for a reaction represents Enthalpy , Entropy is the extent of randomness in a system, Spontaneity is that condition that a reaction takes place without outside help, Gibb's free energy is the difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature and Saturated solution in which no more solute can be dissolved in the solvent.
Which properties will define chemical reaction?Thermodynamically chemical reactions will be define by considering the properties like entropy, enthalpy, free energy, internal energy, temperature and many more.
Enthalpy of the reaction tells about the total amount of heat released or absorbed during a chemical reaction, and it is calculated as sum of the internal energy plus the product of the pressure and volume for a reaction.Entropy of any reaction tells about the randomness and uncertainty present within the molecule or atoms.Spontaneity of any chemical reaction tells about the ease of completion of that reaction. Gibb's free energy is the total energy involved in that reaction and represented as difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature.Saturated solutions are those solutions in which all solute get completely dissolved, no solute will remain undissolved.Hence correct answers are Enthalpy , Entropy ,Spontaneity, Gibb's free energy and Saturated solutions.
To know more about saturated solutions, visit the below link:
https://brainly.com/question/4529762
If 0.1 M solution of CH3COOH of acetic acid will beis 0.01 % ionized in aqueous solution,the ionization constant
a. 10^-7 .
b. 10^-5 .
c. 10^-3 .
d. 10^-9
Answer:
its answer b
Explanation:
A 15.0 mL solution of Sr(OH)₂ is neutralized with 21.1 mL of 0.350 M HCl. What is the concentration of the original Sr(OH)₂ solution?
Answer:
0.246 M
Explanation:
The reaction that takes place is:
Sr(OH)₂ + 2HCl → SrCl₂ + 2H₂OFirst we calculate how many HCl moles reacted, using the given volume and concentration:
0.350 M * 21.1 mL = 7.385 mmol HClThen we convert HCl moles into Sr(OH)₂ moles, using the stoichiometric coefficients of the balanced reaction:
7.385 mmol HCl * [tex]\frac{1mmolSr(OH)_2}{2mmolHCl}[/tex] = 3.692 mmol Sr(OH)₂Finally we calculate the concentration of the original Sr(OH)₂ solution:
3.692 mmol Sr(OH)₂ / 15.0 mL = 0.246 MWhat's a house hold item that has nuclear energy
Answer:
Electricity, Weapons, Medicine · Food Treatments, ect.
Which of the following behaviors might indicate a patient is drug seeking?
A. A patient wants to avoid a specific medication because of
potential side effects.
B. A patient explains that she is from out of town and needs a
specific medicine because she left her prescription at home.
C. A patient fears her new prescription will conflict with another
medication she's currently taking.
D. A patient thinks she needs a smaller dose of her prescription
because it gives her headaches.
SUBMIT
Answer:
B is correct :)
Explanation:
Trust me I just took the test
The reduction of iron(III) oxide () to pure iron during the first step of steelmaking, ()()() is driven by the high-temperature combustion of coke, a purified form of coal: ()()() Suppose at the temperature of a blast furnace the Gibbs free energies of formation of and are and , respectively. Calculate the maximum mass of pure iron that can be produced by the combustion of of coke. Round your answer to significant digits.
Answer:
hello your question is incomplete attached below is the complete question
answer : To 2 significant digits = 5500 kg
Explanation:
Given
C(s) + O2 (g) ----------> CO2 ( g )
mass of CO2 = 8.9 * 10^6 g
number of moles = 8.9 * 10^6 / 12 = 7.416 * 10 ^5 mol
same amount of moles is needed by O2 hence
attached below is the detailed solution
Why do we test for free chlorine in drinking water?
Answer:
The presence of free chlorine in drinking water is correlated with the absence of most disease-causing organisms, and thus is a measure of the potability of water
What is the main function of burette?
Answer:
I think it A
Explanation:
Answer:
its d i think
Explanation:
which formula can be used to calculate the molar mass of ammonia
Answer:
Since there are 3 Hydrogen atoms present, the formula mass of H is 1.0 × 3 = 3.0 g/mol. Therefore, by adding them up, the formula mass of ammonia is: [14.0 g/mol + 3.0 g/mol] = 17.0 g/mol.