Answer:
Trial 1: Heat lost by the metal = -4100 J
Trial 2: Heat lost by the metal = -4042 J
Trial 3: Heat lost by the metal = -3940 J
Explanation:
Assuming that all of the heat lost by the metal is transferred to the water and no heat is lost to the surroundings; Heat lost by metal = heat gained by water. Qmetal = -Qwater
Note: If the experiment was carried out in a calorimeter of known heat capacity, some heat is lost to the calorimeter.
Hence, Qmetal = -(Qwater + Qcalorimeter)
Quantity of heat, q = mass * specific heat capacity * temperature change
Trial 1
mass of water = 70.001 g
specific heat capacity of water = 4.184 J/g/°C
Initial temperature of water = 24.2 °C
final temperature of mixture = 38.2 °C
Temperature change of water = 38.2 - 24.2 = 14.0 °C
Heat gained by water = -(70.001 * 4.184 * 14.0) = -4100 J
Therefore, heat lost by the metal = -4100 J
Trial 2
mass of water = 70.008 g
specific heat capacity of water = 4.184 J/g/°C
Initial temperature of water = 24.0 °C
final temperature of mixture = 37.8 °C
Temperature change of water = 37.8 - 24.0 = 13.8 °C
Heat gained by water = -(70.008 * 4.184 * 13.8) = -4042 J
Therefore, heat lost by the metal = -4042 J
Trial 3
mass of water = 70.271 g
specific heat capacity of water = 4.184 J/g/°C
Initial temperature of water = 23.2 °C
final temperature of mixture = 36.6 °C
Temperature change of water = 36.6 - 23.2 = 13.4 °C
Heat gained by water = -(70.271 * 4.184 * 13.4) = -3940 J
Therefore, heat lost by the metal = -3940 J
A 0.500-gram sample of a weak, nonvolatile monoprotic acid, HA, was dissolved in sufficient water to make 50.0 milliliters of solution. The solution was then titrated with a standard NaOH solution. Predict how the calculated molar mass of HA would be affected (too high, too low, or not affected by the following laboratory procedures. Explain each of your answers.
a. After rinsing the buret with distilled water, the buret is filled with the standard NaOH solution; the weak acid HA is titrated to its equivalence point.
b. Extra water is added to the 0.500-gram sample of HA.
(a) An indicator that changes color at pH 5 is used to signal the equivalence point.
(b) An air bubble passes unnoticed through the tip of the buret during the titration.
Answer:
Follows are the solution to the given points:
Explanation:
It is expected to be too low a calculated molecular weight. It is because NaOH is diluted throughout washing with distilled water. It means that its measured intensity would be too high. Mwt implies Mwt now. Oh, Mwt. It's low. If the water becomes inserted throughout the acid HA, the molarity Across would not be impacted as the acidic mole remains unchanged despite water added to the acidic Ha. It's going to be much too big a molecular weight. Its measurement indicates the middle state at PH=5, well before this neutral point, so that if the NaOH reading is less, and the value of the strength of HA would consequently become lower. So m/Mwt=low shows Mwt=high.Its real measurement will be less because of the air pocket in the office. Even so, because of an unknown bubble interpretation, more is removed. Its intensity of acid is, therefore, less measured, and thus Mwt is also too high.How many moles of copper are in 1.51 x 1024 Cu atoms?
2.51 mol Cu
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Using Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:Step 1: Define
1.51 × 10²⁴ atoms Cu
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
Set up: [tex]\displaystyle 1.51 \cdot 10^{24} \ atoms \ Cu(\frac{1 \ mol \ Cu}{6.022 \cdot 10^{23} \ atoms \ Cu})[/tex]Multiply/Divide: [tex]\displaystyle 2.50747 \ mol \ Cu[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
2.50747 mol Cu ≈ 2.51 mol Cu
What do most mollusks have?
C
Answer:
C- A foot
Particularly a muscular foot.
Answer/Explanation
you"re right they have a foot
Muscular foot for creeping or burrowing. Some also have a head with sense organs.
did u need someone to confirm it or what
when oxygen is available what happens immediately after glycolysis?
NADH IS FORMED
PYRUVATE IS PRODUCED
Oxidative phosphorylation
None of above
Guys pleaaasse i need an answer my final exam will be hours from now
Answer:
NADH is formed
Explanation:
If oxygen exists in the system, pyruvate goes into mitochondrial matrix in order to perform kreb's cycle and forms NADH
Otherwise, pyruvate forms into lactate acid.
Good luck on your final exam
Questlon 23 of 30
What is the term for a large group of people with similar characteristics such
as educational background and income level?
A. An interest group
B. A social class
C. A social culture
O D. A political party
SUBMIT
Which of the following has the strongest hydrogen bonds?
Group of answer choices
C2H6
HF
CH4
H2Se
Answer:
first and the last one hope this helps
Explanation:
number the steps for balancing equations:
O Use coefficients to increase the atoms on each side.
O Check to make sure you have the same number of each type of atom on each side.
O Count the atoms on each side.
O Identify the atoms on each side.
Explanation:
In balancing chemical equations, the law of conservation of matter must be strictly obeyed.
By the virtue of this, the following steps are usually taken:
First identify the atoms on each side of the expression. This to know the number of species to balance. Then count the atoms on each side. Then using appropriate number as the coefficients, increase the atom on each side until there are equal numbers on both sides. Finally, check to make sure we have the same number of each type of atom on each side.Answer:
the answer would be 3 4 2 1
Explanation:
What kind of intermolecular forces act between a hydrogen cyanide molecule and a potassium cation?
If there is more than one type of intermolecular force that acts, be sure to list them all, with a comma between the name of each force.
(dipole, hydrogen-bonding, dispersion, ion-dipole)
Answer:
ion-dipole
Explanation:
Let us remember that the potassium cation is an ion, a positive ion to be precise.
There is a dipole existing in the hydrogen cyanide molecule. The positive end of the dipole is on hydrogen while the negative end of the dipole is on the cyanide moiety.
The only possible interaction between the potassium cation and the hydrogen cyanide is an ion dipole interaction. The cation interacts with the cyanide moiety having a partial negative charge in the molecule.
If you have 2 moles of an element, how many particles do you have?
Answer:
1.204×10^24 particles of element
Explanation:
1mol=6.02×10^23 number of particles (in this case an element)
2mol=(6.02×10^23)×2 particles of the element
=1.204×10^24 particles of element
*be careful aware significant digits
What is MnF3 + AL ? If anyone would
Be so kind
How many moles of NaCl are created as a result of decomposing 12 grams of NaClO3? (molar mass of Na=23, Cl=35, O=16)
Answer: 0.113 moles of NaCl are created as a result of decomposing 12 grams of [tex]NaClO_3[/tex].
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} NaClO_3=\frac{12g}{106.5g/mol}=0.113moles[/tex]
The balanced chemical equation for decomposition of [tex]NaClO_3[/tex] is:
[tex]2NaClO_3\rightarrow 2NaCl+3O_2[/tex]
According to stoichiometry :
2 moles of [tex]NaClO_3[/tex] give = 2 moles of [tex]NaCl[/tex]
Thus 0.113 moles of [tex]NaClO_3[/tex] give =[tex]\frac{2}{2}\times 0.113=0.113moles[/tex] of [tex]NaCl[/tex]
Thus 0.113 moles of NaCl are created as a result of decomposing 12 grams of [tex]NaClO_3[/tex].
A student pours a 10.0mL sample of a solution containing HC2H3O2(pKa=4.8) and NaC2H3O2 into a test tube. The student adds a few drops of bromocresol green to the test tube and observes a yellow color, which indicates that the pH of the solution is less than 3.8 . Based on this result, which of the following is true about the relative concentrations of HC2H3O2 and NaC2H3O2 in the original solution?
Answer:
[HC2H3O2] > NaC2H3O2
Explanation:
The concentration of [tex]\rm HC_2H_3O_2[/tex] has been higher than the concentration of [tex]\rm NaC_2H_3O_2[/tex].
The pKa has been defined as the acid constant that has been used for the determination of the strength of the acid. The higher the pKa value, the weaker the acid has been.
The [tex]\rm HC_2H_3O_2[/tex] has the pka value 4.8 depicting the solution has been a pH 4.8. With the addition of [tex]\rm NaC_2H_3O_2[/tex], the pH has been shifted towards the acidic condition, thus the Hydrogen concentration has been higher.
The change in the pH has been resulted in the reduction in the pH from the basic to acidic condition. Since the concentration of the [tex]\rm HC_2H_3O_2[/tex] has been higher than the [tex]\rm NaC_2H_3O_2[/tex] concentration, the pH has been shifted towards the more acidic condition.
Thus, the concentration of [tex]\rm HC_2H_3O_2[/tex] has been higher than the concentration of [tex]\rm NaC_2H_3O_2[/tex].
For more information about the pH of the solution, refer to the link;
https://brainly.com/question/11936640
How many lead atoms in Pb(OH) 4 ?
4 in hydrogen 4 in oxygen
Explanation:
hope this helps
What is the chemical formula for Sulfuric acid
Answer:
H₂SO₄
have a great day
Answer:
Explanation:
The chemical formula for Sulfuric acid is H₂SO₄
Priscilla was building a circuit that used copper wires to connect a battery to a light bulb. As she connected the final wire from the light bulb back to the battery, the light bulb turned on. Priscilla knew that current was now flowing through her closed circuit. What makes the current in the circuit flow? pls help !!!
Answer:
The voltage or potential difference
Explanation:
What makes current flow in a circuit is the voltage or the potential difference.
This force is supplied by the battery or the mains electrical circuit.
Every circuit requires the voltage to drive current through When a circuit is complete, the battery is able to overcome any resistance by the generating enough voltage which is the force to drive the current through.Kp/Kc for reaction for the equilibrium, A(g) ⇌ C(g)+B(g), is _______.
(Kc is the equilibrium constant in terms of concentrations, Kp is the equilibrium constant in terms of pressures, R is the gas constant, T is the temperature)
Select one:
(RT)2
(RT)-1
(RT)-2
(RT)-1.5
RT
RT
by using relation between Kp and Kc we get the above answer
Esters are formed from the reaction of an alcohol and a carboxylic acid. Identify the alcohol and carboxylic acid combination necessary to make each pictured ester.
Answer:
In this practical, students explore the formation of esters through the ability of different alcohols to react with organic acids. Together, the class can quickly produce a range of esters on a test tube scale, with a variety of interesting smells to sample and compare
The pictured ester can be prepared by the combination of ethanol and propionic Acid. The name of the ester in the picture will be ethyl propanoate.
What are esters?Chemicals called esters are created when an oxoacid reacts with a hydroxyl molecule, such as alcohol or phenol. Esters are widely used. The fatty acid esters of glycerol are the majority of naturally occurring fats and oils.
When an ester reacts with either an amine or alcohol, the reaction is referred to as aminolysis; when an ester reacts with water, it is referred to as hydrolysis of ester. Esters are primarily utilized in flavorings and fragrances, but they can also be employed as solvents in the chemical industry.
Therefore, ethanol and propionic acid can be combined to create the ester shown.
To learn more about esters, refer to the link:
https://brainly.com/question/28203011
#SPJ2
The question is incomplete. Your most probably complete question is given below:
The image of the ester is attached below
When fat comes in contact with sodium hydroxide, it produces soap and glycerin. Determine whether this is a physical change or a chemical change. Explain your
Answer: Chemical change
Explanation:
Physical change is a change where there is a change in size , shape etc and no new products are formed.
Chemical change is a change where there is a change in chemical composition as new products are formed.
Example: Formation of soap and glycerin from fat and sodium hydroxide is a chemical change as the chemical bonds are getting rearranged to form new products.
A student collected a 1.28 g sample of Magnesium. How many atoms of Mg are in his sample?
A student did an experiment that called for 1.24 x 1024 molecules of CaO. What is the mass of her reactant?
A student reacted 0.0405 g of glucose (C6H12O6). How many molecules of glucose did he react?
what is the mass in grams of 0.40 moles of sodium borohydride nabh4
Answer:
15.12g
Explanation:
Given parameters:
Number of moles = 0.4moles
Unknown:
Mass of the compound = ?
Solution:
To solve this problem;
Mass = number of moles x molar mass
Molar mass of NaBH₄ = 23 + 10.8 + 4(1) = 37.8g/mol
Mass of the compound = 0.4 x 37.8 = 15.12g
Answer:
The answer is 15.12 g but if you are taking this test on ck12 make sure you round it to 15 like it says on the directions :) good luck
What is the IUPAC name of the following compound?
Explanation:
none because they can not be mixed together
How many grams are in 4.58x1023 atoms of oxygen?
A digital camera stores images as
A.
digital information.
B.
light.
C.
analog images.
D.
all of these
Answer: A) digital information.
Data is stored in binary fashion as 1s and 0s. If you string enough of them together, you can convey many forms of messages. If you send a message to some kind of storage medium (such as a hard drive or flash drive), then you can retrieve that message at a later date. In effect, you're sending a message to yourself, more or less. By "message", I mean the information about each pixel color that forms the entire image.
In contrast, an analog camera or film camera stores images on film that is to be processed at a later time. Though something like polaroid cameras develop the image fairly quickly without need of a darkroom. Both analog and digital methods involve the use of light to capture the image, and this is true about our eyes needing light as well just to see in general. However, light itself isn't used as a storage method.
\ helppppp
Many organisms on Earth exhibit similar ____________.
Question 2 options:
nonliving
characteristics
time
single-celled
Answer:
characteristics i believe
In table below, there are descriptions of an experiment on samples of three different chemical compounds. Decide whether the compound is ionic or molecular, if you can. If there is not enough information to decide, choose can't decide in the third column.
compound description lonic or molecular?
1 Compound 1 is a yellow-white solid. When heated to melting, it forms an oily yellow liquid, which is a good electrical insulator.
2 Compound 2 is a hard grayish-white solid. A small 250 mg sample of it is put into a quartz tube and heated strongly. It starts to melt at 1055. °C.
3 Compound 3 is a yellow solid made up of clusters of needle-like crystals. It's a good electrical insulator when solid, but if crushed and dissolved in water, the solution is a good conductor.
Answer:
Compound 1- molecular solid
Compound 2- ionic solid
Compound 3- ionic solid
Explanation:
An ionic solid has a high melting point and does not conduct electricity in solid state. Rather, it's solution or melt is a good electrical conductor.
On the other hand, a molecular solid is a poor conductor of electricity. It has a low melting point and does not easily dissolve in water.
How many atoms are present in 0.035 moles?
Answer:
[tex]2.11x10^{22}atoms[/tex]
Explanation:
Hello!
In this case, considering the Avogadro's number, which relates the number of particles and one mole, we can infer that 1 mole of any element contains 6.022x10²³ atoms as shown below:
[tex]\frac{6.022x10^{23}atoms}{1mol}[/tex]
Thus, we compute the number of atoms in 0.035 moles as shown below:
[tex]atoms=0.035mol*\frac{6.022x10^{23}atoms}{1mol} \\\\atoms=2.11x10^{22}atoms[/tex]
Best regards!
What's the purpose of electro cleaning by using electrolysis?
Answer:
Electrolytic cleaning is a method of removing soil, scale or corrosion products from a metal surface by subjecting it as an electrode to an electric current in an electrolytic bath. It is a form of electroplating that can be applied to all electric conductive materials.
PLEASE HELP PLEASE LLEASE HELP, WILL MARK BRAINLIEST!!!
Which of the following elements will NOT reach an octet when in a bond?
Answer:
Hydrogen
Explanation:
Red blood cells are constantly being produced in your body. Another body system cooperates with the cardiovascular system in the production of these cells. What is this system and how does it cooperate?
Can some please help me?
1) Balance the equation Fe2O3 + H2SO4 → Fe2(SO4)3 + H2O.
What is the mole ratio of H2SO4 and H2O in the equation?
1:3
3:2
2:1
3:3
2)Balance the equation Mg + Mn2O3 → MgO + Mn.
What is the mole ratio of Mg and Mn in the equation.
1:1
2:1
3:2
4;2
1. The mole ratio of H2SO4 and H2O in the equation = 3:3
2. The mole ratio of Mg and Mn in the equation = 3:2
Further explanationGiven
Reaction
1. Fe2O3 + H2SO4 → Fe2(SO4)3 + H2O
2. Mg + Mn2O3 → MgO + Mn.
Required
Balanced equation
Solution
1. Fe₂O₃ + H₂SO₄ → Fe₂(SO₄)₃ + H₂O
Give a coefficientaFe₂O₃ + bH₂SO₄ → Fe₂(SO₄)₃ + cH₂O
Make an equationFe, left = 2a, right=2⇒2a=2⇒a=1
S, left=b, right=3⇒b=3
H, left = 2b, right = 2c⇒2b=2c⇒2.3=2c⇒c=3
The equation becomes :
Fe₂O₃ + 3H₂SO₄ → Fe₂(SO₄)₃ + 3H₂O
2. Mg + Mn₂O₃ → MgO + Mn.
Give a coefficientaMg + Mn₂O₃ → bMgO + cMn.
Make an equationMn, left=2, right=c⇒c=2
O₂, left=3, right=b⇒b=3
Mg, left = a, right=b⇒a=b⇒a=3
The equation becomes :
3Mg + Mn₂O₃ → 3MgO + 2Mn.