Answers
Related Questions
An endothermic dissolution process a. absorbs energy as heat and has positive enthalpy of solution. b. releases energy as heat and has positive enthalpy of solution. c. absorbs energy as heat and has negative enthalpy of solution. d. releases energy as heat and has negative enthalpy of solution.An endothermic dissolution process a. absorbs energy as heat and has positive enthalpy of solution. b. releases energy as heat and has positive enthalpy of solution. c. absorbs energy as heat and has negative enthalpy of solution. d. releases energy as heat and has negative enthalpy of solution.
Answers
Answer:
a. absorbs energy as heat and has positive enthalpy of solution.
Explanation:
A reaction can either be exothermic or endothermic. An endothermic reaction, as the dissolution described in the question, is that which absorbs heat energy from the surroundings in order to start the reaction.
Because an endothermic reaction makes heat lost from the surroundings, the enthalpy (∆H) of the solution will be positive (+). ∆H is got by finding the difference between the enthalpy of the reactants and products and since the enthalpy of a product in endothermic reaction is more, the enthalpy change (∆T) will be positive.
A student measured the pH of his soda and found it to be 4.5.
Calculate the [H3O+] in the soda.
Answers
Answer:
0.0111 M
Explanation:
pH = 4.5
[H3O+] = ?
Relationship between both quantitiesis given by:
pH = -log₁₀ [H3O+]
-pH = log₁₀ [H3O+]
-4.5 = log₁₀ [H3O+]
[H3O+] = e ^ (-4.5)
[H3O+] = 0.0111 M
If 36g of Al react with 34L of Oz, how many moles of Al2O3 are produced?
4Al +302 --> 2Al2O3
145 moles
0.667 moles
0.165 moles
101 moles
Answers
Answer:
.........................................................................................................................................................................................................................................................................................................................................................................................................................................................
Explanation:
If 36g of Al react with 34L of Oz, 0.667 moles of Al2O3 are produced. The correct option is b, 0.667 moles
What are moles?The mole is a SI unit of measurement that is used to calculate the quantity of any substance.
[tex]\rm 4Al +3O_2 -- > 2Al_2O_3[/tex]
Step1- calculate the moles of aluminum
The mass of Al is 36 g
The molar mass of Al is 27
[tex]\rm Number\;of \;moles= \dfrac{mass}{molar\;mass}\\\rm Number\;of \;moles\;of\;Al = \dfrac{36}{27} = 1.33\;mol[/tex]
Step2- calculate the moles of oxygen
The mass of O₂ is 34 L
[tex]\rm 1 L = \dfrac{1}{22.4 }[/tex]
[tex]\rm Number\;of \;moles\;O_2= \dfrac{34}{22.4} = 1.51[/tex]
The limiting reagent is 1.33 MOL. By the rule of stoichiometry, four moles of Al produced 2 moles of Al.
[tex]\rm \dfrac{1.33}{2} = 0.665 \;moles[/tex]
Thus, the correct option is b. 0.667 moles.
Learn more about moles
https://brainly.com/question/26416088
#SPJ2
If the temperature and amount of gas stays constant, what will happen to the pressure of a gas if the volume of the container decreases?
Answers
For Fe, its atomic number is 26 and its mass number is 56. How many neutrons does it have?
Answers
Answer:
the number of neutrons available is 30
Explanation:
Given that
The atomic number is 26
And, the mass number is 56
We need to determine the number of neutrons does it have
So, the number of neutrons is
= Mass number - atomic number
= 56 - 26
= 30
Hence, the number of neutrons available is 30
The same would be considered and relevant
CuSO4 + 2NaBr --> CuBr2 + Na2SO4 ? How many grams of CuSO4 are needed to react with 1.80 x 1024 molecules of NaBr?
Answers
Answer:
[tex]238.5gCuSO_4[/tex]
Explanation:
Hello there!
In this case, by considering the given chemical reaction, it is possible for us to calculate the required grams of CuSO4 by considering its molar mass of 159.6 g/mol, the given molecules of NaBr, the Avogadro's number and the 1:2 mole ratio between these two in order to set up the following stoichiometric set up:
[tex]1.80x10^{24}moleculesNaBr*\frac{1molNaBr}{6.022x10^{23}molecules NaBr}*\frac{1molCuSO_4}{2molNaBr} *\frac{159.6gCuSO_4}{1molCuSO_4}\\\\=238.5gCuSO_4[/tex]
Best regards!
What type of molecule is shown below?
H H
| |
H-C-C-0-H
|
Η Η
A. Ether
B. Aldehyde
C. Ketone
D. Alcohol
Answers
The type of molecule which is shown in the given question is alcohol, due to presence of hydroxyl group.
What are functional groups?Funcional groups are those specific groups which after attaching to any compound changes the property of that compound and then that compound will known by the propeties of that functional group.
Given molecule has the molecular structure CH₃-CH₂-OH, means in this molecule hydroxyl group is present which defines the general properties of alcohol.
Hence given molecule is an alcohol.
To know more about functional groups, visit the below link:
https://brainly.com/question/493841
What is the name of P2O in Chemistry?
Answers
P2O : Summary
Code P2O
Molecule name 3-PROP-2-YN-1-YL-1,3-OXAZOLIDIN-2-ONE
Synonyms 1-(PROP-2-YNYL)-OXAZOLIDINE-2-ONE
Systematic names Program Version Name ACDLabs 10.04 3-prop-2-yn-1-yl-1,3-oxazolidin-2-one OpenEye OEToolkits 1.5.0 3-prop-2-ynyl-1,3-oxazolidin-2-one
In general, agitation causes the dissolving rate of most solutes to:
A- remain the same
B- increase
C- vary unpredictably
D-decrease
Answers
PLEASE ANSWER!! DUE TONIGHT!! 10 POINTS!!
Find the density of a cube (to the nearest tenth) with a side of 4 cm. and a mass of 1235 grams. (You do not need to include units in your answer.)
Answers
Answer:
19.3
Explanation:
V=4^3 a^3, to find volume with sides
p= 1235/64, Mass/ Volume= Density
all metals are minerals
a. true
b. false
Answers
Answer:
B. False is the rite answer
Calculate the volume in L of 11.6 moles of Neon at 120 K when it has a pressure of 25.9 atm
Answers
Answer:
The volume of the gas is approximately 4.41 liters
Explanation:
The details of the data of the Neon gas are;
The number of moles of Neon gas present, n = 11.6 moles
The temperature of the sample of Neon gas, T = 120 K
The pressure of the sample of the Neon gas, P = 25.6 atm
By the ideal gas equation, we have;
P·V = n·R·T
Where;
R = The universal gal constant = 0.08205 L·atm·mol⁻¹·K⁻¹
Therefore, we get;
V = n·R·T/P
Which gives;
V = 11.6 moles × 0.08205 L·atm·mol⁻¹·K⁻¹ × 120 K/(25.9 atm) ≈ 4.4097915 L
The volume of the gas, V ≈ 4.41 L.
What is the ion found in a basic solution?
A. OH +
B. H+
C. OH-
D. H-
answer ASAP plz
Answers
Select the correct structure that
corresponds to the name.
4-bromo-5-chlorocyclohexene
Answers
Answer: a
Explanation:
Please help im testing and need an answer as soon as possible
Kaya collects the data shown in the table.
A 2-column table with 3 rows. The first column labeled Quantity has entries Voltage, Current, Resistance. The second column labeled Value has entries 6.0 volts, 0.3 Amperes, empty.
What is the resistance in the circuit?
0.05
1.8
5.7
20
Answers
Answer:
20
Explanation:
not sure please correct me if im wrong
Answer:
20
Explanation:
Got it right on time 4 learning
The greenhouse gas released into the atmosphere as a result of livestock digesting their food is called carbon dioxide
True
False
Answers
Answer:
False
Explanation:
Cows and other livestock release methane, which is a gas like Carbon Dioxide, but not the same thing, even though it does contribute into Carbon Dioxide.
When workers stop working entirely, it is called a(n)
Answer here
SUB
Answers
Answer:
Explanation:
When workers stop working entirely, it is called either a strike or retirement, depending on the circumstances under which it is done. A strike is a mass refusal of employees to work, because they are not satisfied.
Retirement on the other hand happens when the employee reaches certain age, after which he/she can leave the job and get a pension,.
I can't do Miscellaneous calculations!
E.g.
How many moles of oxygen atoms are present in 2.5 mole of water molecules?
Answers
take the unknown (the one that the qn is asking for) and ratio it with the known variable
and then put in the mol that you know for the known variable and just do math to get the answer for the unknown
What is the concentration of a sodium hydroxide solution if 14.5 mL of it are exactly neutralized by 30.0 mL of a 0.500 M hydrochloric acid solution?
Answers
Answer:
1.03 M
Explanation:
Step 1: Write the balanced equation
NaOH + HCl ⇒ NaCl + H₂O
Step 2: Calculate the reacting moles of HCl
30.0 mL (0.0300 L) of 0.500 M HCl react.
0.0300 L × 0.500 mol/L = 0.0150 mol
Step 3: Calculate the moles of NaOH that react with 0.0150 moles of HCl
The molar ratio of NaOH to HCl is 1:1. The moles of NaOH that react are 1/1 × 0.0150 mol = 0.0150 mol.
Step 4: Calculate the molar concentration of NaOH
0.0150 moles of NaOH are in 14.5 mL (0.0145 L).
M = 0.0150 mol/0.0145 L = 1.03 M
If a book has a weight of 23.2 N on Earth, what is its mass?
Answers
Answer: Mass is 2,37 kg
Explanation: Weight G = mg, and g = 9.81 m/s² on Earth.
m = W/g = 23.2 N / 9.81 m/s²
What is the pOH of a solution with [OH-] = 1.4 x 10-13?
O A. -13.15
B. 14.00
C. 12.85
D. 13.15
Answers
Answer:
C. 12.85
Explanation:
just did
an organism that a parasite lives in or on is a
A. prey
B. host
C. consumer
D. prey
Answers
Measurements of half-life make radioactive isotopes useful for
Answers
How many moles of gallium chlorate, Ga(ClO3)3, must react in order to produce 674 kJ of energy according to the following reaction? 2 Ga(ClO3)3 à 2 GaCl3 + 9 O2 DH = - 130.4 kJ
Answers
Answer:
10.3 mol Ga(ClO₃)₃
Explanation:
Let's consider the following balanced thermochemical equation.
2 Ga(ClO₃)₃(s) ⇒ 2 GaCl₃(s) + 9 O₂(s) ΔH = - 130.4 kJ
According to the balanced thermochemical equation, 130.4 kJ of heat are released when 2 moles of gallium chlorate react. The number of moles of gallium chlorate that must react to produce 674 kJ of energy is:
674 kJ × 2 mol Ga(ClO₃)₃/130.4 kJ = 10.3 mol Ga(ClO₃)₃
Thermochemical equations are chemically balanced equations that take into account both the energy change and the physical states of all reactants and products. Energy is a reactant in an endothermic process, whereas it is a product in an exothermic reaction. Here the moles of Ga(ClO₃)₃ is 10.3 mol.
Let's consider the following balanced thermochemical equation.
2Ga(ClO₃)₃(s) ⇒ 2GaCl₃(s) + 9O₂(s) ΔH = - 130.4 kJ
According to the balanced thermochemical equation, 130.4 kJ of heat is released when 2 moles of gallium chlorate react. The number of moles of gallium chlorate that must react to produce 674 kJ of energy is:
674 kJ × 2 mol Ga(ClO₃)₃ / 130.4 kJ = 10.3 mol Ga(ClO₃)₃
To know more about thermochemical equation, visit;
https://brainly.com/question/10384873
#SPJ6
is zinc an example of a element or compound?
Answers
Answer:
Zinc is an element.
Explanation:
Compounds are composed of two or more elements
Answer:
element
Explanation:
zinc is an element with atomic number 30
Which rule for assigning oxidation numbers is correct?
a.)Hydrogen is usually -1
b.)Oxygen is usually -2
c.)A pure group 1 element is +1
d.)A monatomic ion is 0
Answers
Answer:
Answer... Option B. Oxygen is usually -2; except in Peroxides
HELPPP ASAP 10 POINTSS
Which feature of a sound wave directly affects the pitch of the sound? (Pitch is whether it is sounds low like a rumble of thunder or high like a bird chirping)
Question 3 options:
frequency
wavelength
amplitude
longitude
Answers
Answer:
wavelength
Explanation:
Iodine-131 half life 8.040 how long will it take for a 40 gram sample of iodine-131 to decay to 0.75 grams
Answers
Answer:
See explanation below
Explanation:
To get this, we need to apply the general expression for half life decay:
N = N₀e(-λt) (1)
Where:
N and N₀ would be the final and innitial quantities, in this case, masses.
t: time required to decay
λ: factor related to half life
From the above expression we need λ and t. To get λ we use the following expression:
λ = t₁₂/ln2 (2)
And we have the value of half life, so, replacing we have:
λ = 8.04 / ln2 = 11.6
Now, we can replace in (1) and then, solve for t:
0.75 = 40 exp(-11.6t)
0.75 / 40 = exp(-11.6t)
ln(0.01875) = -11.6t
-3.9766 = -11.6t
t = -3.9766 / -11.6
t = 0.34 daysWhat is the pH of the solution if the [H3O+] concentration is 2.5 X 10-4 M?
HELP I'M DESPERATE! NO LINK!
Answers
Answer:
3.60
Explanation:
To calculate the pH of any solution, use the formula;
pH= -log[ concentration ] and for this case take pH= -log[H3O+]
= -log[2.5x10^-4]
therefore pH= 3.60
The idea of pH mainly applies in the determination of the nature of various solutions to the used in the chemical analysis. The correct pH must be determined in order to get accurate results. Ionic equillibria mostly involves the calculations involving pH which is normally obtained after determination of equilibrium concentrations.
How much Pb(NO3)2 would need to be added to 100 mL of water to make a saturated solution at 40°C.
Answers
Answer:
70g of Pb(NO3)2 would need to be added
Explanation:
As you can see in the solubility graph of lead nitrate, Pb(NO₃)₂, the solubility of this salt (That is, the maximum amount of the salt that can be dissolved in 100g of the solvent producing a homogeneous solution) is 70g in 100g of water = 70g of the salt in 100mL of water.
A saturated solution is also defined as solubility: The maximum amount of a solute that can be dissolved in a solvent.
That means:
70g of Pb(NO3)2 would need to be added