The relative humidity on a starry summer night is determined as 91%.
Dry bulb depression temperature
The dry bulb depression temperature is calculated as follows;
ΔT = 19⁰C - 18⁰C = 1⁰C
at dry bulb temperature of 18⁰C and depression temperature of 1⁰C, the relative humidity is determined as 91%.
Thus, the relative humidity on a starry summer night is determined as 91%.
Learn more about relative humidity here: https://brainly.com/question/1129115
#SPJ1
28. After 3 substances are mixed, an odor emits
a. chemical change
b. physical change
c. thermal energy is used
a do
Answer:
a. chemical change
Explanation:
A chemical change can cause an odor, however a physical change cannot, and the use of thermal energy will only make an object colder, not give it an odor.
HELP 20 POINTS
What is the frequency of an Electromagnetic wave has with wavelength 2.94 x 10^-8 cm?
Which of the physical processes below result in the formation of metamorphic rocks
i dont see any processes below
Answer:
Heat and pressure
Explanation:
got it on study island
Which part of the immune system can be "trained" using vaccines?
Will give brainliest
the formula of calcium oxide is CaO. What is the formula of the ionic compound containing calium abd sulfate ions
Answer:
[tex]CaS[/tex]
Explanation:
Hello!
In this case, since calcium's oxidation state when forming ionic bonds is +2 and sulfur's oxidation state when bonding those bonds is -2, for the required formula we write:
[tex]Ca^{2+}S^{2-}[/tex]
Now, since they have the same charge number, we infer the ionic compound formed when they bond is calcium sulfide:
[tex]CaS[/tex]
Best regards!
True or False: Most metals are found to occur naturally in their uncombined states.
Answer:
I think it's true. But I'm not sure
Answer:
True
Explanation:
What type of reaction occurs between an element and a compound?
Answer:
exothermic reaction
Explanation:
because it occurs in the presence of heat
A certain reaction requires 0.250 moles of Na2SO4. How
much sodium sulfate should the chemist weigh out to perform
the reaction?
The chemist weigh out 35.51 g Na2SO4
Further explanationGiven
0.250 moles of Na2SO4
Required
weight of Na2SO4
Solution
A mole is a number of particles(atoms, molecules, ions) in a substance
This refers to the atomic total of the 12 gr C-12 which is equal to 6.02.10²³, so 1 mole = 6.02.10²³ particles
Moles of a substance can also be determined from its molecular weight
[tex]\tt mol=\dfrac{mass}{MW}[/tex]
For 0.250 moles of Na2SO4, mass =
[tex]\tt mass=mol\times MW\\\\mass=0.25\times 142,04 g/mol\\\\mass=35.51~g[/tex]
A saturated hydrocarbon having molecular formula CnH2n+2 diffuses through a porous membrane twice as fast as sulphur dioxide. Calculate the volume occupied by the hydrocarbon at27°C and 2atm ?
Help me fast !
Answer:
12.3 L
Explanation:
Now we have that the rate of diffusion of the saturated hydrocarbon is R1
Rate of diffusion of sulphur dioxide is R2
Molar mass of hydrocarbon is M1
Molar mass of sulphur dioxide is 64 gmol-1
From Graham's law;
R1/R2 = √64/M1
2/1 =√64/M1
(2/1)^2 = (√64/M1)^2
4/1 = 64/M1
4M1 =64
M1 = 16
To obtain the number of moles of the gas;
(n*12) + (2n + 2) 1 = 16
12n + 2n + 2 = 16
14n + 2 = 16
14n = 16 - 2
n = 14/14
n = 1
Hence the hydrocarbon is CH4
Volume occupied by CH4 at STP = 22.4 L
Hence;
P1 = 1 atm
T1 = 273 K
V1 = 22.4 L
T2 = 300 K
P2 = 2 atm
V2 = ?
P1V1/T1 = P2V2/T2
P1V1T2 = P2V2T1
V2 = P1V1T2/P2T1
V2 = 1 * 22.4 * 300/2 * 273
V2 = 12.3 L
The volume occupied by the hydrocarbon at 27 °C and 2 atm is 12.31 L
Let the hydrocarbon be initially at standard temperature and pressure (STP)
Thus, we can obtain the new volume of the hydrocarbon by using the combined gas equation as illustrated below:
Initial volume (V₁) = STP = 22.4 L Initial pressure (P₁) = STP = 1 atmInitial temperature (T₁) = STP = 273 KFinal temperature (T₂) = 27 °C = 27 + 273 = 300 KFinal pressure (P₂) = 2 atmFinal volume (V₂) =?P₁V₁ / T₁ = P₂V₂ / T₂
(1 × 22.4) / 273 = (2 × V₂) / 300
22.4 / 273 = (2 × V₂) / 300
Cross multiply
273 × 2 × V₂ = 22.4 × 300
546 × V₂ = 6720
Divide both side by 546
V₂ = 6720 / 546
V₂ = 12.31 L
Thus, the volume occupied by the hydrocarbon at 27 °C and 2 atm is 12.31 L
Learn more about gas laws:
https://brainly.com/question/25967416
Which of the following is NOT a property of sodium
1. Sodium is a reactive METAL
2. Sodium is very SOFT
3. Sodium is a reactive GAS
4. Sodium forms a WHITE coating
Answer:
3
Explanation:
Sodium is not a gas, it is a Alkali Metal. I recommend studying the sections of the periodic table to help remember what each element should be.
Hope this helps.
A radical is a reactive intermediate with a single ____________ electron, formed by ____________ of a covalent bond. Allylic radicals are stabilized by ____________ , making them ____________ stable than tertiary radicals. A compound that contains an especially weak bond that serves as a source of radicals is called a radical ____________ . Treatment of cyclohexene with N-bromosuccinimide in the presence of light leads to ____________ by ____________ intermediates.
1. A radical is a reactive intermediate with a single ____________ electron, formed by ____________ of a covalent bond.
1. A: Unpaired, and homolysis
2. Allylic radicals are stabilized by ____________ , making them ____________ stable than tertiary radicals.
2. A: Resonance, and more
3. A compound that contains an especially weak bond that serves as a source of radicals is called a radical ____________ .
3. A: Initiator
4. Treatment of cyclohexene with N-bromosuccinimide in the presence of light leads to ____________ by ____________ intermediates.
4. A: Allylic substitution by radical
A precipitate of lead chloride is formed when silver chloride is dissolved in a saturated solution of lead chloride due to g
Answer:
Due to "Common ion effect".
Explanation:
Lead chloride and Silver chloride have an ion in common which is Cl-, when these two solutions are dissolved, more chloride reacts with lead which shifts equilibrium position to the right hence precipitating out.
The pressure of a sample of argon gas was increased from 3.89 atm to 8.73 atm at constant temperature. If the final volume of the argon sample was 18.4 L, what was the initial volume of the argon sample? Assume ideal behavior.
Answer:
41.29 LExplanation:
The initial volume can be found by using the formula for Boyle's law which is
[tex]P_1V_1 = P_2V_2[/tex]
Since we are finding the initial volume
[tex]V_1 = \frac{P_2V_2}{P_1} \\[/tex]
From the question we have
[tex]V_1 = \frac{8.73 \times 18.4}{3.89} = \frac{160.632}{3.89} \\ = 41.293573...[/tex]
We have the final answer as
41.29 LHope this helps you
1
MS-LS1-1, MS-LS1-2
Structure and
Function of Cells
-, -
1. Which of the following is not stated in the cell
theory?
A. Cells are the basic unit of structure and
function in all living things.
B. Animal cells are generally more complex
than plant cells.
C. All living things are composed of cells.
D. All cells are produced from other cells.
Ok
Help me as soon as possible I’m gonna dieeee
Read the word equation: “Propane gas plus oxygen gas produces __________.”
b) Convert the word equation to a chemical equation and complete the reaction. Be sure to balance
the chemical equation.
c) Record the balanced chemical equation on the Student Worksheet.
Answer:
Propane gas plus oxygen gas produces water and carbon dioxide.
Explanation:
This is the initial chemical equation: C3H8 + O2 = CO2 + H2O
This is the balanced chemical equation: C3H8 + 5 O2 = 3 CO2 + 4 H2O
C3H8 + O2 → CO2 + H2O
However, the above equation is not balanced. To balance it, we make use of coefficients to make the number of atoms of each element equal. The balanced equation is as follows:C3H8 + 5O2 → 3CO2 + 4H2O
Learn more: https://brainly.com/question/7181548?referrer=searchResults
Complete the statement of equality.
Answer:
This is not a viable question.
Explanation:
Which force keeps the planets from floating off into space?
Earth’s gravity
the Sun’s gravity
the moon’s gravity
Milky Way’s gravity
Answer:
Suns gravity
Explanation:
Answer: 2021
B
The Sun's gravity
Explanation: Just took the big test
. Bob plants some seeds in a small cup. He puts the cup in the light and waters the soil every day. After 4 days, the seedlings emerge from the soil. What can Bob conclude?
answers in the picture I HAVE TO TURN IN THIS AT 10:30 PLEASE HELP ME OUT
The seedlings exerted an upward pushing force on the soil explains why the
seeds emerged from the soil.
Bob watered the soil in which the seed absorbs the water through the coat ,
the seed coat and embryo begins to enlarge and emerge from the soil.
The hydrated enzymes become active thereby increasing metabolic
activities and energy production which is needed for the growth of the plant.
The energy helps the seed exert an upward force on the soil.
Read more on https://brainly.com/question/2515369
In a double replacement reaction, the ions of two compounds exchange places in an aqueous solution to form two new compounds.
True
False
Answer:
true
Explanation:
Answer:
True
Explanation:
In a displacement reaction, more reactive element displaces less reactive element. Whereas in a double displacement reaction there is exchange of ions of two compounds.
g In this equation stands for the Rydberg energy, and stands for the principal quantum number of the orbital that holds the electron. (You can find the value of the Rydberg energy using the Data button on the ALEKS toolbar.) Calculate the wavelength of the line in the emission line spectrum of hydrogen caused by the transition of the electron from an orbital with to an orbital with . Round your answer to significant digits.
The complete question is attached to this answer
Answer:
2.75 * 10^-5 m
Explanation:
The energy of the absorbed photon = ΔE
ΔE = - Ry (1/n^2 final - 1/n^2initial)
Given that Ry = 2.18 *10^-18 J
nfinal = 9
ninitial =8
ΔE = - 2.18 *10^-18 (1/9^2- 1/8^2)
ΔE = - 2.18 *10^-18 (0.0123 - 0.0156)
ΔE = 7.194 * 10^-21 J
But
ΔE =hc/λ
h = 6.6 *10^-34Js
c= 3 * 10^8 ms-1
λ= the unknown
λ= hc/ΔE
λ= 6.6 *10^-34 * 3 * 10^8/ 7.194 * 10^-21
λ= 2.75 * 10^-5 m
What element needs just a single extra electron to have the same electron configuration as helium?
Answer:
Hydrogen
Explanation:
Helium has an atomic number Z = 2, that is, it has 2 protons. Since it is electrically neutral it also has 2 electrons. Thus, the electron configuration of helium is 1s².
Hydrogen has an atomic number Z = 1, that is, it has 1 proton. Since it is electrically neutral it also has 1 electron. Thus, the electron configuration of hydrogen is 1s¹.
If hydrogen gains a single extra electron to form H¹⁻, it acquires the same electron configuration than helium.
If a system's internal energy increases by 250 kJ after the addition of375 kJ of energy as heat, what was the value ofthe work in the process?
(A) -625 kJ
(B) -125 kJ
(C) 125 kJ
(D) 625 kJ
Answer:
(B) -125 kJ
Explanation:
Going by the First Law of Thermodynamics it states that"
"A system can do work and increase it's internal energy provided we supply heat."
ΔU= q+w-----------1
where U= the internal heat
q= the quantity of heat added or removed from the system
w= the work done
Given
ΔU= 250kJ
q= 375kJ
from equation 1 make w subject of the formula we have
w= ΔU-q
w= 250-350
w= -125kJ
PLEASE HELP WILL GIVE BRAINLIEST
Answer:
Coefficients represents no of moles while subscripts represent no of atoms.
Answer:
Coefficients came before formula . Example = 4CO means there are 4 molecules of carbonmonooxide.
Subscripts came after and below the formula . Example = Oxygen gas in which 2 is a subscript which means there are 2 atoms of Oxygen in 1 molecule of Oxygen i.e. oxygen gas
What statement is not true about the field of science
Answer:
where are the statements?
Explanation:
Are these synthesis decomposition single replacement or double replacement?
Answer:
1. Synthesis
2. Decomposition
3. Single replacement
4. Synthesis
5. Decomposition
6. Synthesis
Explanation:
Kind of a hard picture to look at but let me define each chemical reaction:
Synthesis:
a + b ---> ab In synthesis elements/compounds come together to form new compounds
Decomposition:
ab ---> a + b In decomposition a compound breaks down to form 2 elements/compounds
Single replacement:
a + bc ---> b + ac In a single replacement one element/compound takes the place of another element/compound.
Double replacement
ab + cd ---> ad + bc In a double replacement 2 compounds exchange different elements/compounds.
Now, let's go through the assignment
1. P + O2 --> P4O10 This is a synthesis reaction because the two elements (P and O) came together to form one compound.
2. HgO ---> Hg + O2 This is a decomposition reaction because HgO broke into separate elements Hg and O.
3. Cl2 + NaBr ---> NaCl + Br2 This is a single replacement reaction because chlorine (Cl) replaced the spot of bromine (Br) to bond with sodium (Na).
4. Mg + O2 ---> MgO This is a synthesis reaction because two elements (Mg and O) came together to form one compound.
5. Al2O3 ---> Al + O2 This is a decomposition reactions because Al2O3 broke into separate elements Al and O.
6. H2 + N2 ---> NH3 This is a synthesis reaction because two elements (H and N) came together to form one compound.
I hope this helps!!
- Kay :)
Given chemical equations are of following types which are given in serial order as synthesis,decomposition,replacement,synthesis,decomposition and synthesis reactions respectively.
1. It is a synthesis reaction because the two elements (P and O) came together to form one compound.
2. It is a decomposition reaction because HgO broke into separate elements Hg and O.
3. It is a single replacement reaction because chlorine (Cl) replaced the spot of bromine (Br) to bond with sodium (Na).
4. It is a synthesis reaction because two elements (Mg and O) came together to form one compound.
5. It is a decomposition reactions because aluminium oxide broke into separate elements Al and O.
6. It is a synthesis reaction because two elements (H and N) came together to form one compound.
Learn more about chemical equation,here:
https://brainly.com/question/28792948
#SPJ4
When the volume of a gas is
changed from 3.6 L to 15.5 L, the
temperature will change from
°C to 87°C.
Assume that the number of moles and the
pressure remain constant.
Be sure to notice that temperatures are
given in °C!
Answer:
-189.55°C
Explanation:
Given data:
Initial volume of gas = 3.6 L
Final volume of gas = 15.5 L
Initial temperature = ?
Final temperature = 87°C (87+273 = 360 K)
Solution:
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
T₁ = V₁T₂ /V₂
T₁ = 3.6 L × 360 K / 15.5 L
T₁ = 1296 L.K / 15.5 L
T₁ = 83.6 K
Kelvin to °C:
83.6 K - 273.15 = -189.55°C
How many grams are in 2.3 x 1024 formula units of KNO3?
390 g KNO₃
General Formulas and Concepts:ChemistryAtomic Structure
Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.MathPre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right Explanation:Step 1: Define
2.3 × 10²⁴ formula units KNO₃
Step 2: Identify Conversions
Avogadro's Number
Molar Mass of K - 39.10 g/mol
Molar Mass of N - 14.01 g/mol
Molar Mass of O - 16.00 g.mol
Molar Mass of KNO₃ - 39.10 + 14.01 + 3(16.00) = 101.11 g/mol
Step 3: Convert
[tex]2.3 \cdot 10^{24} \ formula \ units \ KNO_3(\frac{1 \ mol \ KNO_3}{6.022 \cdot 10^{23} \ formula \ units \ KNO_3} )(\frac{101.11 \ g \ KNO_3}{1 \ mol \ KNO_3} )[/tex] = 386.172 g KNO₃
Step 4: Check
We are given 2 sig figs. Follow sig fig rules and round.
386.172 g KNO₃ ≈ 390 g KNO₃
What's the enthalpy of neutralization and explain briefly how it relates to esterification
Answer:
The enthalpy of neutralization and its relation to esterification is explained below in details.
Explanation:
The conventional enthalpy variation of neutralization is the enthalpy exchange when extracts of an acid and an alkali respond together under conventional circumstances to generate 1 mole of water. Remark that the enthalpy change of neutralization is always estimated per mole of water produced.