The specific heat of metal = 0.897 J/g° C
Further explanationHeat absorbed can be calculated using the formula:
Q = mc∆TQ = heat, J
m = mass, g
c = specific heat, joules / g ° C
∆T = temperature difference, ° C / K
Q = 8.793 J
m = 2 g
∆t = 4.9 °C
[tex]\tt c=\dfrac{Q}{m.\Delta t}\\\\c=\dfrac{8.793}{2\times 4.9}\\\\c=0.897~J/g^oC[/tex]
according to the law of energy conservation, the total amount of energy is constant, then why does the chemical energy in electric cells got used up?
Answer:
The law of conservation of energy states that energy can neither be created nor destroyed - only converted from one form of energy to another.
Explanation:
This means that a system always has the same amount of energy unless it's added from the outside. is the total internal energy of a system.
Each pure substance has characteristic physical and chemical properties that can be used to identify it.
Compare and contrast physical properties and chemical properties of a substance. Give and example for each:
If an ideal gas has a pressure of 5.87 atm,
a temperature of 26.86 ∘C,
and a volume of 77.31 L,
how many moles of gas are in the sample?
Answer:
5.87/26.86=77.31/...Explanation:
after solving this u can find the answer in easy way
How many moles of dinitrogen monoxide are present in 9.3 x 10^22 molecules of this compound?
Answer:
0.15 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities.
From the question we have
[tex]n = \frac{9.3 \times {10}^{22} }{6.02 \times {10}^{23} } \\ = 0.154485...[/tex]
We have the final answer as
0.15 molesHope this helps you
A student with a body temperature of 37℃ holds a piece of ice that has a temperature of -8℃. Which statement best explains what happens?
A. Heat transfers coldness from the ice to the student's hand.
B. Thermal energy transfers heat from the student's hand to the ice.
C. Heat transfers thermal energy from the student's hand to the ice.
D. Thermal energy transfers coldness from the student's hand to the ice.
Answer: C. Heat transfers thermal energy from the student's hand to the ice.
Explanation: It seems confusing; b and c seem to be saying the same thing, but the definition of heat is the transfer of thermal energy from a warmer object to a colder object.
2. Calculate the new molanty of a solution formed when 20 ml of water is added to 100 ml of
0.2M NaOH
Answer:
New molarity = M₂ = 0.167 M
Explanation:
Given data:
New molarity = M₂ = ?
Final volume = V₂ = 100mL + 20 mL = 120 mL
Initial volume =M₁ = 100 mL
Initial molarity =V₁ = 0.2 M
Solution:
M₁V₁ = M₂V₂
0.2 M × 100 mL = M₂ × 100 mL
M₂ = 0.2 M × 100 mL/120 mL
M₂ = 20 M.mL/120 mL
M₂ = 0.167 M
Which element has a smaller atomic radius?
tungsten (74) or oxygen (8)
Answer:
Oxygen
Explanation:
Atomic radius trend
-decreases from left to right
-increases from top to bottom
Tungsten is in period 7, which has a larger atomic radius
Oxygen is in period 2, which is in a lower energy level and is on the right side. Therefore, has a smaller atomic radius.
Give two everyday examples of the thermal energy of a substance being decreased
Answer:
An example of the thermal energy of a substance being decreased is with our food. With the thermal energy of food being decreased it is easier for foods to be eaten comfortably without any damage to the tongue or alimentary canal.
Another good example is in the handling of hot objects in the home. Thermal energy decrease in objects such as iron, pots etc helps to prevent serious burns and injuries.
Answer:
Water turning into ice
juice frozen to make popsicles
Explanation:
When something goes from liquid to a solid, that is a process called freezing. When a object loses thermal energy the particles move slower forming a solid.
Calculate the electrical double layer length for pure water at pH 7. Assume temperature is 300K, and give your answer in units of nm.
Answer:
[tex]$\lambda_D =964 \ nm$[/tex]
Explanation:
We know, the double layer length of pure water is given by :
[tex]$\lambda _{D}= \left(\frac{\epsilon k_B T}{2e^2z^2N_AC_i}\right)^{1/2}$[/tex]
[tex]$\lambda _{D}= \left(\frac{(78.3)\times(8.85 \times 10^{-21})\times (1.38 \times 10^{-23})\times 300}{2 \times(1.6 \times 10^{19})^2 \times 1^2 \times (6.023 \times 10^{23})\times (10^{-7}) \times 1000 }\right)^{1/2}$[/tex]
Since, pH = -log [tex]$H^+$[/tex]
[tex]$[H^+]=10^{-7}$[/tex]
[tex]$\lambda_D = \left(93.05 \times 10^_{-14}\right)^{1/2}$[/tex]
[tex]$\lambda_D = \sqrt{93.05} \times 10^{-7}$[/tex]
[tex]$\lambda_D =9.64 \times 10^{-7}$[/tex]
[tex]$\lambda_D =964 \times 10^{-9} \ m$[/tex]
[tex]$\lambda_D =964 \ nm$[/tex]
A reaction occurs in a calorimeter, resulting in the starting temperature of 38.8 ℃ and final temperature 21.0 ℃. What can you say about the reaction and the enthalpy change (ΔH) during the reaction?
Answer:
hola comoe stas
Explanation:
gracias x los puntos
What bond distance is expected to be longest?
1. A carbon-carbon bond with a bond order of 2
2. A carbon-carbon bond with a bond order of 3
3. A carbon-carbon bond with a bond order of O
4. carbon-carbon bond with a bond order of 1
Answer:
Bond length of C=C is largest(134 pm) because both the carbon atoms have same electronegativity. In case of C=O. and C=N carbon is bonded to highly electronegative atoms so bond length is shoreter as compared to C=C
Question 2 (2 points)
Saved
How many grams of water do will you need to prepare 480 g of 8.5% solution of
C6H12O6
Answer:
[tex]m_w=439.2g[/tex]
Explanation:
Hello!
In this case, since the by-mass percent of a solution is a measure of the mass of the solute over the mass of the solution:
[tex]\%m/m=\frac{m_{solute}}{m_{solution}} *100\%[/tex]
As we know the mass of the solution and the by-mass percent, we can compute the mass of glucose in the 480 g of solution:
[tex]m_{solute}=\frac{\%m/m*m_{solution}}{100\%}[/tex]
Thus, by plugging in the data, we obtain:
[tex]m_{solute}=\frac{8.5\%*480g}{100\%}=40.8g[/tex]
Finally, since the solution is made up of glucose and water, we compute the mass of water as follows:
[tex]m_w=m_{sol}-m_{solute}=480g-40.8g\\\\m_w=439.2g[/tex]
Best regards!
For Hydrogen bonding H atom needs to be bonded to which other atoms?
The movement of water is able to transport minerals and nutrients. Which statement best explains why water is able to do this?
A. Water has a density of one gram per milliliter
B. Water is an excellent solvent
C. Water absorbs heat energy
D. Water is a liquid at room temperature
A 2.4L balloon filled with helium at room temperature 25oC is put into liquid nitrogen
(-196oC). What will the new volume be?
Answer:
V₂ = 0.62 L
Explanation:
Given data:
Initial volume = 2.4 L
Initial temperature = 25°C
Final temperature = -196°C
Final volume = ?
Solution:
Initial temperature = 25°C (25+273 = 298 K)
Final temperature = -196°C ( -196+273 = 77 K)
The given problem will be solve through the Charles Law.
According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.
Mathematical expression:
V₁/T₁ = V₂/T₂
V₁ = Initial volume
T₁ = Initial temperature
V₂ = Final volume
T₂ = Final temperature
Now we will put the values in formula.
V₁/T₁ = V₂/T₂
V₂ = V₁T₂/T₁
V₂ = 2.4 L × 77 K / 298 k
V₂ = 184.8 L.K / 298 K
V₂ = 0.62 L
Which is the largest number? O A. 2.2 x 108 O B. 2.9 O C. 2.5 x 10-5 D. 2.8 x 106
Answer:
2.2 x 10⁸
Explanation:
We are to find the largest number from the given set of numbers:
2.2 x 10⁸
2.9
2.5 x 10⁻⁵
2.8 x 10⁶
The largest number is the first one; 2.2 x 10⁸ ;
2.2 x 100 000 000
the other numbers are far lesser than this number;
Give the name for the molecular compound O3Cl2.
Answer:
dichlorine trioxide
Explanation:
di-2 tri-3 there are three oxygens and two chlorines.
Answer:
Dichlorine Trioxide
Explanation:
The molar mass and molecular weight of Cl2O3 is 118.904.
The heat of vaporization of acetic acid is . Calculate the change in entropy when of acetic acid condenses at .
The question is incomplete, the complete question is;
The heat of vaporization ΔHv of acetic acid HCH3CO2 is 41.0 /kJmol. Calculate the change in entropy ΔS when 954.g of acetic acid condenses at 118.1°C. Be sure your answer contains a unit symbol. Round your answer to 3 significant digits.
Answer:
-1.67 JK-1
Explanation:
Since Heat of vaporization of acetic acid = 41.0 kJ/mol
Therefore:
Heat of condensation of acetic acid = -41.0 kJ/mol
Mass of acetic acid = 954 g
Temperature of condensation = 118.1 °C or 391.1 K
Number of moles of acetic acid = 954 g/60g/mol = 15.9 moles
Heat evolved during condensation = 15.9 moles * -41.0 kJ/mol = -651.9 KJ
Entropy change (ΔS) = Heat evolved/ Temperature = -651.9 KJ/391.1 K
Entropy change (ΔS) = -1.67 JK-1
How many alkyl substituents does N-ethyl-N-methylaniline have?
one
two
O three
o eight
none
Answer:
Two.
Explanation:
Hello!
In this case, considering the attached picture wherein you can see the presence of the parent chain as aniline, we can see radicals at the nitrogen, named by N-ethyl and N-methyl which are the present alkyl substituents. In such a way, the benzene ring is not considered an alkyl radical because it belongs to the parent chain on aniline and therefore, N-ethyl-N-methylaniline has two alkyl substituents.
Best regards!
There are two alkyl substituents attached to the nitrogen; one ethyl and one methyl group
Aniline consists of a benzene ring to which an -NH2 moiety is attached. Usually, it is possible for the any of the two hydrogen atoms in the -NH2 moiety to become substituted leading to N-alkylated product.
In the compound N-ethyl-N-methylaniline, there are two alkyl substituents attached to the nitrogen; one ethyl and one methyl group as shown in the image attached to this answer.
Learn more: https://brainly.com/question/6284546
Please help me it’s due today at 6:00pm please help me please please
Answer:
a) an opposing force act on it
i hope its true
A party balloon filled with helium deflates to 2/3 of its original volume in 8.0 hours. How long will it take an identical balloon filled with the same number of moles of air (ℳ = 28.2 g/mol) to deflate to 1/2 of its original volume?
Answer:
The easy way to do this is to assume the number of moles. Make it a number easily divided by both 2 and 3, so say 6. Now you can have numbers to plug in to Graham's Law to find the second rate, then use the second rate to find the time. Does that make sense?
What's is the definition of an atom
Atom, smallest unit into which matter can be divided without the release of electrically charged particles. It also is the smallest unit of matter that has the characteristic properties of a chemical element. As such, the atom is the basic building block of chemistry.
What property of gases confirms that the space between the particles of gas is significantly larger than when the same substance is in a liquid state?
A. Mobility
B. Reactivity
C. Volatility
D. Compressibility
Answer:
D. Compressibility
Explanation:
A substance that functions to prevent rapid, drastic changes in the pH of a body fluid by changing strong acids and bases into weak acids and bases is called a(n):
A. Buffer
B. Salt
C. Enzymes
D. Coenzyme
among the intermolecular forces,which forces are typically the weakest
Answer:
The London dispersion force is the weakest intermolecular force. The London dispersion force is a temporary attractive force that results when the electrons in two adjacent atoms occupy positions that make the atoms form temporary dipoles.
What is an aqueous solution and what does it do?
Answer:
An Aqueous solution is used to reference any solution where water acts as the solvent. A lot of substances can dissolve in water including acids and bases and when they do this they become aqueous solutions.
Aqueous solutions are denoted by the symbol (aq) in solutions as shown in this reaction below where Sodium Chloride is dissolved in water;
NaCl(s) → Na+(aq) + Cl-(aq)
Aqueous solutions are capable of conducting electricity if electrolytes are the ones dissolved in the water.
There are however some substances that cannot form aqueous solutions because they cannot dissolve well in water for example, organic substances like oils.
Compounds of copper(II) are generally colored, but compounds of copper(I) are usually colorless. Use crystal field theory to explain why this is true.
Answer:
See explanation
Explanation:
The crystal field theory assumes the interaction between the central metal ion and ligands to be purely electrostatic.
The five d orbitals remain degenerate until they are surrounded by ligands which split the degeneracy of the d orbitals depending on the crystal fields formed to give either square planar, octahedral, tetrahedral or other kinds of crystal fields.
The electronic configuration of Cu II ion is 1s2 2s2 2p6 3s2 3p6 3d9. Its colour arises from an incomplete d orbital which makes d - d electron transition possible.
On the other hand, the electron configuration of copper I is 1s2 2s2 2p6 3s2 3p6 3d10. We can see that the d orbital is completely filled. Hence copper I ion has no color due to its completely filled d- orbitals
Sean plated an unknown metal onto his silver earring which initially weighed 1.41 g. He constructs an electrolytic cell using his ring as one of the electrodes. After running the cell, 0.022 moles of the unknown metal was plated onto his ring and the mass of the ring increased to 3.952 g. What is the atomic weight of the unknown metal in g/mol
Answer:
115 g/mol
Explanation:
Step 1: Given data
Initial mass of the earring (mi): 1.41 gFinal mass of the earring (mf): 3.952 gMoles of the unknown metal deposited (n): 0.022 molStep 2: Calculate the mass of the unknown metal deposited
An earring is plated in an electrolytic cell. The mass of the unknown metal deposited can be calculated using the following expression.
m = mf - mi
m = 3.953 g - 1.41 g
m = 2.54 g
Step 3: Calculate the molar mass (M) of the unknown metal
0.022 moles of the metal have a mass of 2.54 g. The molar mass of the metal is:
M = m/n
M = 2.54 g / 0.022 mol
M = 115 g/mol
HELP ME PLEASE I will mark brainliest
Answer:
Nice pic there
Explanation:
No need
A chemist dissolves 249.mg of pure perchloric acid in enough water to make up 380.mL of solution. Calculate the pH of the solution. Be sure your answer has the correct number of significant digits.
Answer:
pH = 2.18
Explanation:
Perchloric acid (HClO₄) is a strong acid. This means that in an aqueous solution it completely dissociates into H⁺ and ClO₄⁻ species.
First we convert 249 mg HClO₄ into moles, using its molecular weight:
249 mg HClO₄ ÷ 100.46 mg/mmol = 2.49 mmol HClO₄Because it is a strong acid, 2.49 mmol HClO₄ = 2.49 mmol H⁺
We calculate the molar concentration of H⁺:
2.49 mmol H⁺ / 380 mL = 6.52x10⁻³ MFinally we calculate the pH of the solution:
pH = -log[H⁺] = -log(6.52x10⁻³)pH = 2.18