Answer: 1 mole = 6.02 x 10^ 23
Explanation:
The number of atoms in one mole of helium is equal to 6.022×10²³ He atoms.
What is Avogadro's number?Avogadro’s constant can be demonstrated as the proportionality factor that utilizes to count the number of particles such as ions, molecules, atoms, or ions in a sample of the substance.
Avogadro's number can be defined as the approximate count of nucleons in 1 gram of substance. The value of the Avogadro number is the mass of 1 mole of a compound, in grams, and is the number of nucleons in one particle.
The value of Avogadro’s number is equal to 6.022×10²³ per mole.
Given, the number of moles of the helium = 1 mol
Helium is a monatomic gas so it contains only one atom in its one molecule.
The number of atoms of Helium in one mole = 6.022 × 10²³
Therefore, the total number of atoms contained in a 1 mole sample of
helium is 6.022 × 10²³.
Learn more about Avogadro's number, here:
brainly.com/question/11907018
#SPJ6
why do we need digital technology in school?
Answer: See explanation
Explanation:
Digital technologies refers to the electronic tools, or devices that can be used to generate data, store them or process data. e.g. mobile phones, ebooks etc.
Digital learning makes use of technology. Effective use of digital learning tools can help increase the engagement of students. This csn.aksi be used by the teachers to enhance personalized learning and also improve the lesson plans.
Digital technology can enhance collaboration, and communication with the students. The use of videos, robots, virtual classrooms, augmented reality and other technologies can bring about fun and foster inquisitiveness.
HELP ASAP PLEASE!!! :)
Answer:
Alkane
Explanation:
Alkenes have CH in their condensed formulas and alkynes have C in their condensed formulas. There are only CH3 and CH2 so it's an alkane.
Which element had the smallest atomic radius
Answer:
helium is the answer
Explanation:
helium is the smallest element in francium is the largest hope this helps
A strong acid, such as hydrochloric acid cannot be poured down a sink because it will react and dissolve the metal in the pipes. Yet a strong base, commonly found in drain cleaner, can be poured down a sink. A strong acid can be neutralized with a strong base, creating a salty water solution. What will happen when 10.0 g of hydrochloric acid were mixed with 10.5 grams of calcium hydroxide?
Answer:
15.2 grams of calcium chloride are produced and HCl is the limiting reactant.
Explanation:
Hello there!
In this case, according to the described scenario, it is possible to realize that the reaction between hydrochloric acid and calcium hydroxide is:
[tex]2HCl+Ca(OH)_2\rightarrow CaCl_2+2H_2O[/tex]
Whereas there is a 2:1 mole ratio of the acid to the base. In such a way, with the given masses, we can compute how much calcium chloride product is produced due to the chemical reaction via stoichiometry:
[tex]m_{CaCl_2}^{by HCl}=10.0gHCl*\frac{1molHCl}{36.46gHCl}*\frac{1molCaCl_2}{2molHCl} *\frac{110.98gCaCl_2}{1molCaCl_2} =15.2gCaCl_2\\\\m_{CaCl_2}^{by Ca(OH)_2}=10.5gHCl*\frac{1molCa(OH)_2}{74.09gCa(OH)_2}*\frac{1molCaCl_2}{1molCa(OH)_2} *\frac{110.98gCaCl_2}{1molCaCl_2} =15.7gCaCl_2[/tex]
Whereas we infer that the correct amount is 15.2 g since HCl is the limiting reactant as it produces the fewest grams of the desired product. Consequently, the calcium hydroxide is the excess reactant here.
Regards!
Using the rules that we developed in this chapter (ARIO), we might have expected these two compounds to have the same pKa. Nevertheless, they are different. Salicylic acid is apparently more acidic than its constitutional isomer. Can you offer an explanation for this observation
Answer:
The correct answer is
- after deprotonation carboxylic acid stabilizes by binding -OH group with hydrogen bonding in salicylic acid and while it's not possible with its constitutional isomer (para-hydroxy benzoic acid).
The more electronegative atoms are replaced by the H atom of the carboxylic group and form more stabilize carboxylic acid which not takes place in para-hydroxy benzoic acid.
how do you think a device could change the sound that we hear? Make sure you use vocabulary such as frequency, energy and amplitude
Answer:
good luck tho
Explanation:
Walking up a flight of stairs and noticing that it gets warmer as you climb
higher is an example of *
5 points
Conduction
Convection
Radiation
Brain damage
What is the volume of 0.200 moles of O2 gas at STP?
Answer:
4.48 L O2
Explanation:
At STP, a mole of any gas contains 22.4 liters. Therefore, we simply have to multiply the amount of moles by 22.4
0.2mol O2 ( 22.4 L) = 4.48 L O2
You have a bag of chips at a constant pressure of 1 Atm with a volume of .5 L and a temperature of 10C. The bag is left under the sun for a couple of hours at a temperature of 35 C, what will its new volume be?
Answer:
0.54 L
Explanation:
Given that,
Initial volume, V₁ = 0.5 L
Initial temperature, T₁ = 10°C = 283 K
Final temperature, T₂ = 35 C = 308 K
We need to find the final volume. The relation between the volume and temperature is given by :
[tex]\dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}\\\\V_2=\dfrac{V_1T_2}{T_1}\\\\V_2=\dfrac{0.5\times 308 }{283}\\\\V_2=0.54\ L[/tex]
So, the new volume is 0.54 L.
How did the industrial Revolution impact the population of peppered moths in Britain?
The Industrial Revolution caused the proportions of each color morph in the population to become equal.
The light-colored moths became more common
The dark-colored moths became more common
The Industrial Revolution caused the proportions of each color morph in the population to become unequal
Answer:
due to the pollution the light months tended to stand out against the the wood that was dark due to the smoke the darker months population grew due to the fact that they were more harder to see for the predators
Answer:
The dark colored months became more common
Explanation:
Thats the answer !
The trait that shows up in the first generation.
Recessive
Dominant
Ok
Answer:
Dominant
Explanation:
hope this help
Only 5 minutes to answer!
Why are the weather satellites important on Mars?
Answer:
they can track the weather which can show if it would be posssible to live or have life on mars
Explanation:
g At elevated temperatures, molecular hydrogen and molecular bromine react to partially form hydrogen bromide: H 2 (g) Br 2 (g) 2HBr (g) A mixture of 0.682 mol of H 2 and 0.440 mol of Br 2 is combined in a reaction vessel with a volume of 2.00 L. At equilibrium at 700 K, there are 0.516 mol of H 2 present. At equilibrium, there are ________ mol of Br 2 present in the reaction vessel.
Answer: At equilibrium , there are 0.274 moles of [tex]Br_2[/tex]
Explanation:
Moles of [tex]H_2[/tex] = 0.682 mole
Moles of [tex]Br_2[/tex] = 0.440 mole
Volume of solution = 2.00 L
Initial concentration of [tex]H_2[/tex] = [tex]\frac{0.682}{2.00}=0.341 M[/tex]
Initial concentration of [tex]Br_2[/tex] = [tex]\frac{0.440}{2.00}=0.220 M[/tex]
Equilibrium concentration of [tex]H_2[/tex] = [tex]\frac{0.516}{2.00}=0.258 M[/tex]
The given balanced equilibrium reaction is,
[tex]H_2(g)+Br_2(g)\rightleftharpoons 2HBr(g)[/tex]
Initial conc. 0.341 M 0.220 M 0 M
At eqm. conc. (0.341-x) M (0.220-x) M (2x) M
Given : (0.341-x) M = 0.258 M
x= 0.083 M
Thus equilibrium concentartion of [tex]Br_2[/tex] = (0.220-0.083) M = 0.137 M
Thus moles of [tex]Br_2[/tex] at equilibrium = [tex]0.137M\times 2.00L=0.274mol[/tex]
At equilibrium , there are 0.274 moles of [tex]Br_2[/tex]
8. How much heat will be released when
18.6 g of hydrogen reacts with excess O2
according to the following equation?
Answer:
15 is it
Explanation:
A solution is made by dissolving 62.42 g of ammonium sulfate in enough
water to make 50.0 mL of solution. What is the molarity of this solution?
(**Use only numerical answers with 3 significant figures. The units are given
in the question.)
Answer:
9.46 M
Explanation:
Molarity is a measure of the molar concentration of a solution. It can be calculated by the following formula
Molarity = number of moles/volume
Using moles = mass/molar mass
Molar Mass of Ammonium sulfate (NH₄)₂SO₄ =
{14 + 1(4)}2 + 32 + 16(4)
= {14 + 4}2 + 32 + 64
= 18(2) + 96
= 36 + 96
= 132g/mol
mole = mass/molar mass
mole = 62.42 ÷ 132
mole = 0.473mol
- Molarity = mole ÷ volume
Volume = 50.0 mL = 50/1000 = 0.05 L
Molarity = 0.473 ÷ 0.05
Molarity = 9.46 M
Write a formula and balanced equation for the following: solid copper metal reacts with aqueous silver nitrate to produce solid silver metal and aqueous copper Nitrate. How do I know if it will form copper (I) nitrate CuNO3 or copper (II) nitrate Cu(NO3)2 ?
Explanation:
copper (II) nitrate
Illustrate variety of substances of which an element can be part:
metal --> blue solution --> blue solid --> black solid --> blue solution (again) --> metal (again).When solid copper reacts with aqueous silver nitrate, the products are copper (II) nitrate and solid silver. and carbon monoxide gas produces solid iron and carbon dioxide gas.
Iron has a density of 7.87 g/cm^3. What is the mass of 55.2 cm^3 of iron?
Answer: Formula: Mass = (Volume)(Density)
Iron Density = 7.87 g/cm^3
Volume of Iron = 55.2 cm^3
Mass=(V)(D)
Mass= (55.2 cm^3) x (7.87 g/cm^3)
Mass= 434,42 g
Explanation:
Iron has a density of 7.87 g/cm³. 434,42 g is the mass of 55.2 cm³ of iron.
What do you mean by density ?The term density is defined as the measurement of how closely a material is packed together.
It is also defined as the mass per unit volume. Density Symbol is D or ρ Density Formula is ρ = m/V, where ρ is the density, m is the mass of the object and V is the volume of the object.
Density is an important because it allows us to find out what substances will float and what substances will sink when placed in a liquid.
Formula:
Mass = (Volume)(Density)
Given:
Iron Density = 7.87 g/cm³
Volume of Iron = 55.2 cm³
Mass=(V)(D)
Mass= (55.2 cm³) x (7.87 g/cm³)
Mass= 434,42 g
Thus, Iron has a density of 7.87 g/cm³. 434,42 g is the mass of 55.2 cm³ of iron.
To learn more about the density, follow the link;
https://brainly.com/question/29775886
#SPJ2
Question 6 of 10
How much energy is required to vaporize 2 kg of gold? Use the table below
and this equation: Q = mLvapor
Substance
Latent Heat
Fusion
(melting)
(kJ/kg)
Melting
Point
(°C)
Latent Heat
Vaporization
(boiling) (kJ/kg)
Boiling
Point
(°C)
Aluminum
400
660
1100
2450
Copper
207
1083
4730
2566
Gold
628
1063
1720
2808
Helium
52
-270
21
-269
Lead
24.5
327
871
1751
Mercury
11.4
-39
296
357
Water
335
0
2256
100
Answer: Q = mlvap
Q = (2 kg)(1 kmol/197 kg)(1,000 mol/1 kmol)
Q = 10.15 kJ
2126 joules of energy in form of thermal energy is required to vaporize 2 kg of gold.
What is thermal energy?Thermal energy is defined as a type of energy which is contained within a system which is responsible for temperature rise.Heat is a type of thermal energy.It is concerned with the first law of thermodynamics.
Thermal energy arises from friction and drag.It includes the internal energy or enthalpy of a body of matter and radiation.It is related to internal energy and heat .It arises when a substance whose molecules or atoms are vibrating faster.
These vibrating molecules and atoms collide and as a result of which heat is generated in a substance , more the collision of particles , higher is the thermal energy.
Amount of heat is calculated as, Q=2×1063 =2126 joules as per the given formula.
Learn more about thermal energy,here:
https://brainly.com/question/18989562
#SPJ5
How many molecules of N204 are in 85.0 g of N2O4?
Answer:
5.56 x 10^23
Explanation:
Just convert and cancel out.
85 g N2O4 x 1 mol/92.01 g x 6.02 x 10^23 molecules /1 mol
Nitrous oxide (N2O), more commonly known as laughing gas, is used as a mild sedatitive during various dental procedures.As a gas, it has a densityof 1.977 x 10-3g/mL.Wheniron is exposed to oxygen it forms rust (Fe2O3), which is a solid and has a density value of 5.25 g/mL.Why are the density values so different among these substances?
a)The metal atoms weigh more than the atoms of the gas.
b)The metal forms metallic bonds which are more greatly affected by gravity, increasing the mass.
c)The metal is a solid, and solids weigh more based on the principles of their states of matter.
d)There are fewer gas particles than solid particles in the same volume.
Answer:
B.
Explanation:
The metal forms metallic bonds which are more greatly affected by gravity, increasing the mass.
identify the solute in the following: carbon dioxide dissolved in water
a. water
b. carbon dioxide
c. none of the above
d. carbon dioxide and water
Answer:
B
Explanation:
its solute state is gas and dissolve in (solvent) liquid which is water
Use the following Balanced Equation to complete the question: 2 Al + 6 HBr → 2 AlBr3 + 3 H2
If you have 10 moles of Al how many moles of H2 can be produced?
*Will give Brainly!*
The reason for using 1-propanol as the solvent of choice for recrystallization is that triphenylphosphine oxide is more soluble in 1-propanol than the alkene product because triphenylphosphine oxide can use its oxygen to hydrogen-bond to 1-propanol, whereas the alkene has no hydrogen-bonding capability. Triphenylphosphine oxide, therefore, is removed based on its polarity and H-bonding ability.
a. True
b. False
Answer:
True
Explanation:
Hydrogen bonding is a bond that exists between hydrogen and a highly electronegative element such as oxygen, nitrogen, fluorine etc.
The greater solubility of the triphenylphosphine oxide owes to the hydrogen bonded interaction between it and the 1-propanol.
The alkene lacks such hydrogen bonded interaction because it does not have a highly electronegative atom in its structure.
Hence, triphenylphosphine oxide is removed based on its polarity and hydrogen bonding ability.
Which factor contributes the most to the rates of diffusion and effusion between two gases in a mixture?
a)The size of the particles.
b)The molar mass of the particles.
c)The interactions between the particles.
d)The relative volume of the particles to each other.
Answer:
b)The molar mass of the particles.
Explanation:
The rate of effusion of a gas is inversely proportional to the square root of its molar mass (Graham's law), a relationship that closely approximates the rate of diffusion. As a result, light gases tend to diffuse and effuse much more rapidly than heavier gases.
What will be the pH of a buffer solution containing an acid of pKa7.5, with an acid concentration exactly one fourth of that of the conjugate base
Answer: pH of buffer solution is 8.1
Explanation:
The formula for the Henderson–Hasselbalch equation is:
[tex]pH=pK_a+\log\frac{[A^-]}{[HA]}[/tex]
[tex]pH[/tex] is the concentration of [tex][H^+][/tex]
[tex]pK_a[/tex] is the acid dissociation constant,
[tex]A^-[/tex] and [tex]HA[/tex] are concentrations of the conjugate base and starting acid.
Putting in the values we get:
[tex]pH=7.5+\log\frac{x}{\frac{x}{4}}[/tex]
[tex]pH=8.1[/tex]
Thus pH of buffer solution is 8.1
Lab: Measuring pH Table or
Lab Report please ( just link it ) please
Answer:
sorry my phone died lol but here are the answers
<3
What is orbit? A. An increase in centripetal motion and mass friction. B. Resistance of an object to avoid friction. C. Gravity causing a curved path as an object tries to go straight. D. How well an object floats.
Answer:
C. gravity causing a curved path as an object tries to go straight.
Why do scientists think that liquid water might have once existed on Mars?
Answer: The discovery of three buried lakes. Scientists think that a long time ago there were lakes and rivers, etc on Mars. Now of course, you can't see any visible water sources on the surface.
Answer:
Almost all water on Mars today exists as ice, though it also exists in small quantities as vapor in the atmosphere.[5] What was thought to be low-volume liquid brines in shallow Martian soil, also called recurrent slope lineae may be grains of flowing sand and dust slipping downhill to make dark streaks.The only place where water ice is visible at the surface is at the north polar ice cap. Abundant water ice is also present beneath the permanent carbon dioxide ice cap at the Martian south pole and in the shallow subsurface at more temperate conditions. More than 5 million km3 of ice have been detected at or near the surface of Mars, enough to cover the whole planet to a depth of 35 meters. Even more ice is likely to be locked away in the deep subsurface.
Some liquid water may occur transiently on the Martian surface today, but limited to traces of dissolved moisture from the atmosphere and thin films, which are challenging environments for known life. No large standing bodies of liquid water exist on the planet's surface, because the atmospheric pressure there averages just 600 pascals , a figure slightly below the vapor pressure of water at its melting point; under average Martian conditions, pure water on the Martian surface would freeze or, if heated to above the melting point, would sublime to vapor. Before about 3.8 billion years ago, Mars may have had a denser atmosphere and higher surface temperatures, allowing vast amounts of liquid water on the surface, possibly including a large ocean that may have covered one-third of the planet.Water has also apparently flowed across the surface for short periods at various intervals more recently in Mars' history. Aeolis Palus in Gale Crater, explored by the Curiosity rover, is the geological remains of an ancient freshwater lake that could have been a hospitable environment for microbial life.Many lines of evidence indicate that water ice is abundant on Mars and it has played a significant role in the planet's geologic history.The present-day inventory of water on Mars can be estimated from spacecraft images, remote sensing techniques (spectroscopic measurements, radar, etc.), and surface investigations from landers and rovers.Geologic evidence of past water includes enormous outflow channels carved by floods, ancient river valley networks, deltas and lakebeds,and the detection of rocks and minerals on the surface that could only have formed in liquid water. Numerous geomorphic features suggest the presence of ground ice (permafrost)and the movement of ice in glaciers, both in the recent past and present. Gullies and slope lineae along cliffs and crater walls suggest that flowing water continues to shape the surface of Mars, although to a far lesser degree than in the ancient past.Although the surface of Mars was periodically wet and could have been hospitable to microbial life billions of years ago, the current environment at the surface is dry and subfreezing, probably presenting an insurmountable obstacle for living organisms. In addition, Mars lacks a thick atmosphere, ozone layer, and magnetic field, allowing solar and cosmic radiation to strike the surface unimpeded. The damaging effects of ionizing radiation on cellular structure is another one of the prime limiting factors on the survival of life on the surface. Therefore, the best potential locations for discovering life on Mars may be in subsurface environments. Large amounts of underground ice have been found on Mars; the volume of water detected is equivalent to the volume of water in Lake Superior. In 2018, scientists reported the discovery of a subglacial lake on Mars, 1.5 km (0.93 mi) below the southern polar ice cap, with a horizontal extent of about 20 km (12 mi), the first known stable body of liquid water on the planet.Understanding the extent and situation of water on Mars is vital to assess the planet’s potential for harboring life and for providing usable resources for future human exploration. For this reason, "Follow the Water" was the science theme of NASA's Mars Exploration Program (MEP) in the first decade of the 21st century. NASA and ESA missions including 2001 Mars Odyssey, Mars Express, Mars Exploration Rovers (MERs), Mars Reconnaissance Orbiter (MRO), and Mars Phoenix lander have provided information about water's abundance and distribution on Mars.Mars Odyssey, Mars Express, MRO, and Mars Science Lander Curiosity rover are still operating, and discoveries continue to be made.
A balloon has a pressure of 3.5atm and a volume of 4.2L. What will the volume of the balloon be if the pressure is increased to 7.0atm? Assume that temperature remains constant. SHOW ALL WORK FOR FULL CREDIT!
The volume of the balloon is 2.1L.
What is volume?Volume is the amount of space the matter occupies. The SI unit of volume is cubic meter.
Using Boyles law equation,
P1V1 = P2V2
Where P1 and V1 are the initial pressure and volume of the gas
P2 and V2 are the final pressure and volume of the gas
Given:
P1 = 3.5atm
V1 = 4.2L
P2 = 7.0atm
V2 = ?
Solve for V2 ,
V2 = P1V1/P2
V2 = (3.5atm x 4.2 L) / (7.0atm)
= 2.1L
Hence, the volume of the balloon is 2.1L.
To learn more about volume here
https://brainly.com/question/22756604
#SPJ2
Convert 8.19 x 10-14 moles of gold to atoms.
Answer:
4.932018 × 10¹⁰ atoms
Explanation:
Recall that:
1 mole = 6.022 × 10²³ atoms
To change 8.19× 10⁻¹⁴ moles to atoms;
Then, we have:
= (8.19× 10⁻¹⁴× 6.022 × 10²³ atoms)
= 4.932018 × 10¹⁰ atoms