Answer:
Need the choices before i can give answers thanks
Explanation:
Express the answers to these problems in the correct number of
significant figures.
6. 0.042 m. + 1.33 m =
7. 8.90 g - 4.555 g =
8. 60.0 L/5 L =
9.
7.8 cm x 3.5 cm =
10.
5.63 +4.245 - 8.9 =
Answer:
I solved the questions then counted how many significant figures in each answer
eg,
0.042m+1.33m =1.372m
1.372 has 4 significant figures
that's how you do others
Explanation:
6. 1.372m = 4 significant figures
7. 4.345g = 4 significant figures
8. 12L = 2 significant figures
9. 27.3cm = 3 significant figures
10. 0.975 = 3 significant figures
Bill, a lab technician, was asked to measure out sodium hydroxide (NaOH) for an experiment in a research lab. He was given a choice between a beaker, a graduated cylinder, and a buret (shown left). Bill used a graduated cylinder to measure the liquid NaOH because he says, “a graduated cylinder is the most accurate way to measure a liquid!” Do you agree or disagree with Bill? Use significant figures to justify your answer.
Answer:
He is wrong . Most accurate is Buret .
Explanation:
The number of significant figure denotes the level of accuracy of a measurement .
Beaker can measure liquid in mL upto significant figure of 2 . That means it can measure volume in terms of 10 , 20 , 30mL etc . It can not measure 25 mL
accurately . The last figure of 28 mL is read by guess in the question . So it is not an accurate measurement .
Similarly , graduated cylinder can measure liquid upto significant figure of 3 . That means it can measure volume in terms of 11 , 22 , 33 mL etc . It can not measure 25.5 mL accurately . The last figure of 28.3 mL is read by guess in the question . So it is less accurate measurement .
Similarly , buret can measure liquid upto significant figure of 4 . That means it can measure volume in terms of 11.2 , 22.3 , 33.5 mL etc . It can not measure 25.53 mL accurately . The last figure of 28.32 mL is read by guess in the question . So it is most accurate among all the three instrument because it can measure accurately mL upto one tenth of it .
Answer:
No
Explanation:
The number of significant figure denotes the level of accuracy of a measurement .
Beaker can measure liquid in mL upto significant figure of 2 . That means it can measure volume in terms of 10 , 20 , 30mL etc . It can not measure 25 mL
accurately . The last figure of 28 mL is read by guess in the question . So it is not an accurate measurement .
Similarly , graduated cylinder can measure liquid upto significant figure of 3 . That means it can measure volume in terms of 11 , 22 , 33 mL etc . It can not measure 25.5 mL accurately . The last figure of 28.3 mL is read by guess in the question . So it is less accurate measurement .
Similarly , buret can measure liquid upto significant figure of 4 . That means it can measure volume in terms of 11.2 , 22.3 , 33.5 mL etc . It can not measure 25.53 mL accurately . The last figure of 28.32 mL is read by guess in the question . So it is most accurate among all the three instrument because it can measure accurately mL upto one tenth of it .
Hope this helps
at a molecular level describe the differences between a hot object and a cold object
Answer:
.
Explanation:
The hot object are those which have high energy atoms that moves with a very fast energy whereas the cold object are those which have low energy atoms and moves with low speed.
Density Practice
Answer the following questions about density.
1) Density is based on the
and the
of a material
2) A material with a low density tends to
I
3) A material with a high density tends to
4) Bobbing for apples is a game where people try to bite apples from a bucket of water. While in the
water, the apples float. Which is less dense, the apples or the water?
5) A cannonball rolls off of a pirate ship and sinks to the bottom of the ocean. Which was more dense, the
cannonball or the ocean water?
Answer:
1) mass and volume
2) float.
3) Sink
4) Apples
5) Cannonball
Explanation:
1) Density is based on the mass and volume of a material.
2) A material or an object with low density than water or liquid tends to float.
3) A material or an object with high density than water or liquid tends to sink.
4) The apples in the water have less density as they are floating in the water.
5) The cannonball is more dense than the ocean water and the ball sink in the less density water.
In a oxidation–reduction reaction, oxidation and reduction must occur simultaneously. Is this statement true or false?
Answer:
True
Explanation:
Oxidation and reduction always occur simultaneously. Gave example when a substance is oxidized or reduced? 1) The substance gaining oxygen or losing electron is oxidized. 2) The substance losing oxygen ( or gaining electron) is reduced. hope this helps you :)
What concentration of ClO3â results when 967 mL of 0.367 M AgClO3 is mixed with 667 mL of 0.643 M Mn(ClO3)2?
Answer:
0.742M is the concentration of ClO₃⁻
Explanation:
The AgClO₃ contains 1 mole of ClO₃⁻ per mole of compound, but Mn(ClO₃)₂ contains 2 moles of ClO₃⁻ per mole of compound.
The moles of AgClO₃ are:
0.967L * (0.367moles / L) = 0.355 moles AgClO₃ = 0.355 moles of ClO₃⁻
And of Mn(ClO₃)₂:
0.667L * (0.643moles / L) = 0.429 moles Mn(ClO₃) * 2 = 0.858 moles of ClO₃⁻
That means total moles of ClO₃⁻ are:
0.355 moles + 0.858 moles = 1.213 moles ClO₃⁻ that are in 0.967L + 0.667L = 1.634L.
The concentration is:
1.213 moles ClO₃⁻ / 1.634L =
0.742M is the concentration of ClO₃⁻Which of the following correctly describes a mixture? (4 points)
The particles are chemically bondeg together, and they retain their individual physical and chemical pro
The particles are not chemically bonded, and they can only combine in certain set ratios.
The particles do not retain their individual chemical properties, and they can only be separated by chemi
The particles have no set ratio for how to combine, and they can be separated by physical means.
The statement the particles have no set ratio for how to combine, and they can be separated by physical means describes a mixture.
What is mixture?A mixture is made when two or more substances are combined, but they are not combined chemically. The components of a mixture can be easily separated. The components each keep their original properties. The proportion of the components are variables.Physical means like filtration, evaporation, and sublimation can all be used to separate mixtures. There is no chemical reaction that takes place. As a result, it can be physically detached because it is still theoretically divided into its constituent parts.
Hence, we can conclude that option D is the answer.
To learn more about mixture here
https://brainly.com/question/24898889
#SPJ2
Magnesium is an alkaline earth metal with an atomic number of 12. It’s in the third row in the periodic table. Which expression shows one way to find the number of valence electrons in one atom of magnesium?
Answer:
group # = # valence electrons
group 2= 2 valence electrons
Explanation:
Mg is in group #2 and subsequently has 2 valence electrons (electrons on the outermost shell)
A zinc salt, E when
produced a brown gas wiele pungent Smell,
Colourless which repondled a
e glowing splinte
and a residue which was followed to cool.
:) Identify the salt &
ion for the decomposition
of o
..) state what would be observed when the
residue was allowed to Cool
;) write ar
equat
Answer:
The salt is Zn(NO3)2
When the residue is allowed to cool, its colour changes from yellow to white
The equation of the reaction is; 2Zn(NO3)2(s) --->2ZnO(s) + 4NO2(g) + O2(g)
Explanation:
Decomposition of Zn(NO3)2 is one of the routes by which ZnO is obtained. ZnO is a white insoluble powder which has a yellow colour when hot and a white colour when cold. It is an amphoteric substance used as a white pigment in paints and as a filler for rubber.
In a very pure form, it is used in cosmetic powders and creams as well as in medicinal ointments and lotions.
Also recall that NO2 is a brown gas and oxygen gas rekindles a glowing splint.
How many bonds does argon group viii form
A. 0
B. 3
Which one of the following substances would be the most soluble in C6H6 ? Group of answer choices CO2 all of these can dissolve C6H6 C10H22 S8 (sulfur) SiO2
Answer:
C10H22
Explanation:
C6H6 is the molecular formula for Benzene. Benzene is an aromatic hydrocarbon which is obtained from the destructive distillation of coal. Benzene is a colourless volatile liquid with a sweet smell. Its vapor is highly toxic and mildly carcinogenic. It is highly inflammable. Benzene is nonpolar which is insoluble in water. Since benzene is insoluble in water , it will take an insoluble compound to be soluble in benzene since "like dissolves like".
From the options given:
C10H22 which is the molecular formula for Decane would be the most soluble in C6H6. This is because Decane is an alkanes which is an aliphatic hydrocarbon and their physical properties increases with increasing molar mass ( i.e melting points, boiling points , density, polarity) etc. The first mfour member of the family are gases. non-polar liquid starts with th fifth member of the family which is pentane and from hexadecane onwards the members are solids at room temperature. Thus, decane is a non-polar hydrocarbon which is insoluble in water but soluble in benzene
Write an experiment ?
like a lab report or something?
Estimate the percentage growth rate for a population of bacteria that grew from
100 to 6400 in 1 day.
Answer:
r = 4.15
Explanation:
Given:
Number of initial bacteria = 100
Number of Final bacteria = 6400
Find:
Growth rate
Computation:
6400 = 100 × [tex]e^r[/tex]
6400 / 100 = [tex]e^r[/tex]
64 = [tex]e^r[/tex]
Taking natural log both side
r = 4.15
You buy several bags of balloons. On the package, it says that each bag has 100 balloons. He opens the bags and only one of them has 100 balloons inside; the other bags either have too many or too few. How would you describe this sample of bags?
Answer:
Accurate but not precise
Explanation:
The sample of balloon bags can be described as being accurate but not precise.
Recall that accuracy is the closeness of measurements to their true values while precision is the closeness of repeated measurement.
The balloon bags are accurate because it appears that the number of balloons in each bag is not far from the actual number of balloons that should be in them - exactly 100 in one and a few off in others. By the time the average number of balloons is calculated, it will not be far off from 100, if not exactly 100.
However, the sample bags are described as not being precise because of the inconsistency or lack of closeness in the number of balloons in each of them.
A solution of H2SO4(aq)H2SO4(aq) with a molal concentration of 2.55 m2.55 m has a density of 1.151 g/mL.1.151 g/mL. What is the molar concentration of this solution?
Answer:
Molar concentration = 2.35 M (Approx)
Explanation:
Given:
Density of solution = 1.151 g/ml
2.55 molal = 2.55 moles of solute/ kg
Find:
Molar concentration
Computation:
Molar mass of H2SO4 = 2(1.0079) + (32.066) + 4(15.999)
Molar mass of H2SO4 = 98.0778
Molar mass of H2SO4 = 98 g/mol (Approx)
Mass of solution = 2.55(98)g + 1000 g
Mass of solution = 1249.9 gm
Volume of solution = 1249.9 / 1.151 = 1086 ml
Volume of solution = 1.086 L
Molar concentration= 2.55 / 1.086
Molar concentration = 2.35 M (Approx)
Answer:
[H₂SO₄] = 2.35M
Explanation:
Our solute is the sulfuric acid → H₂SO₄
To determine the molar concentration we need the volume of solution.
Mass of solute: moles . molar mass
2.55 mol . 98 g/ 1 mol = 249.9 grams
Mass of solvent: 1 kg (we know this, because data refers about molality, moles of solute in 1kg of solvent)
Mass of solution = solute + solvent → 1000 g + 249.9 g = 1249.9 g
We apply density: Density = Mass / volume
1.151 g/mL = 1249.9 g / mL
mL = 1249.9 g/ 1.151 g/mL = 1086 mL
Molarity → mol/L → 2.55 moles/1.086L = 2.35 M
If you have a cold drink on your hand, how does heat flow from the drink to your hand and from your hand to drink ?
Answer:
If two objects have different temperatures, heat will flow from the warmer object to the colder one. For instance, when you hold an ice cube, heat is transferred from your warm hand to the cold ice and melts it. Your hand feels cold because it is losing heat energy. ... energy by electromagnetic waves.
Hope it helped u if yes mark me BRAINLIEST!
Tysm!
I would appreciate it!
Answer: Because your body heats up the area where it gets cold so that how that works
Explanation:
The equation for photon energy, E, is E=hc/λ
where h = 6.626×10−34 J⋅s (Planck's constant) and c = 2.99×108 m/s (the speed of light).
What is the wavelength, λ, of a photon that has an energy of E = 3.92×10−19 J ?
Answer:
The wavelength, λ, of a photon that has an energy of E = 3.92×10⁻¹⁹ J is 5.054*10⁻⁷ m
Explanation:
The wavelength is defined for every periodic wave, that is, for the type of wave that repeats itself with exactly the same shape every given interval of time. It is the distance between two points from which the wave repeats.
Radiation is the emission, propagation and transfer of energy in any medium in the form of electromagnetic waves or particles.
The energy carried by electromagnetic radiation travels by waves. This energy is transmitted grouped in small "quanta" of energy called photons. The energy of a photon is measured in Joules (J) and is
[tex]E=\frac{h*c}{wavelength}[/tex]
Being:
E=3.92×10⁻¹⁹ Jh= 6.626×10⁻³⁴ J⋅s (Planck's constant) c = 2.99×10⁸ m/s (the speed of light)wavelength=?and replacing:
[tex]3.92*10^{-19}J =\frac{6.626*10^{-34}J.s*2.99*10^{8}\frac{m}{s} }{wavelength}[/tex]
you get:
[tex]wavelength =\frac{6.626*10^{-34}J.s*2.99*10^{8}\frac{m}{s} }{3.92*10^{-19}J}[/tex]
wavelength= 5.054*10⁻⁷ m
The wavelength, λ, of a photon that has an energy of E = 3.92×10⁻¹⁹ J is 5.054*10⁻⁷ m
Convert 200°F into °C
What do the spheres represent in a typical model of an atomic nucleus?
Answer:
Protons and Neutrons
Explanation:
That is what makes up the center of an atom
Defina a fórmula denominada Lei do Gás Ideal, que será usada em todo o trabalho. Indique o que significa cada uma das grandezas presentes na equação e quais são as unidades usadas para cada uma, quando R = 0,082 atm L / K mol.
Explanation:
Ideal gas law is also called gas equation. It shows the behaviour of many gases.
The general gas equation is given by :
PV = nRT
P is pressure in atm
V is volume of gas in litre
n is number of moles
R is gas constant =0.082 atm L/ K-mol
T is temperature in Kelvin
Which types of particles are found in the nucleus of the atom?
Answer:
Protons and neutron are found in the nucleus.
Answer:
The nucleus of the atom contains two types of subatomic particles: protons(have a positive electrical charge) and neutrons (have no electrical charge).
Arrange the following in order of increasing masses of 1 mole of CO32-, PO43-, SO42- Cl- S2- (1)
The kilogram is the SI unit for mass
Answer:
yes
Explanation:
SI unit of mass is kilogram.
Answer:
kg is the S.I unit for mass
Explanation:
Mass is the amount of matter in the substance and is measured with the help of the UNIT (S.I system) Kg.
Which is one way that earth’s atmosphere supports life?
Answer:
The atmosphere protects living things on earth from the sun's harmful ultraviolet radiation.
Explanation:
keeping the earth warm, the atmosphere contains gases that enable the "Greenhouse effect", (it means that they are able to trap the heat that is reflected from the surface of the earth.)
Answer:
It Keeps Earth Warm
Explanation:
what volume of liquid is in the graduated cylinder
Answer: 7.1
Explanation:
Convert 302 K into C
Answer:
302°K = 28.85°C
Explanation:
Formula: °K - 273.15 = °C
0°C is equal to roughly 273°K
Simply plug it into the formula to find your temperature:
302°K - 273.15 = °C
°C = 28.85
Texas Ranchers are not fond of the mesquite tree. The tree invades range land and prevents the growth of other vegetation. Bee keepers, however, prize the nectar from the blooms of the mesquite tree because it makes the sweetest honey (measured in grams of sugar/ per ounce of honey). Can the rancher and the bee keeper live in the same community? Design an experiment to test various flower blooms to produce the same honey as the mesquite's blooms.
Answer:
No.
Explanation:
No, the rancher and the bee keeper can't live on the same place because the rancher need a specific area where there is a lot of vegetation for their animals while the bee keeper needs a lot of trees from which the honey bees collect nectar at the time of blooming. So both need different environment for making high yield and good profit so they can't live in the same community.
You have 263 mL of liquid mercury, what is the mass of mercury that you have?
Answer:3,550.5 g
Explanation:
Mass= density×volume
Mass= 13.5g/m.l×263ml
Mass=3,550.5 g
Please add me the brainleist!!!!!!!!
The study of the universe and how it
evolved is called
Answer:
Hey there!
Cosmology is the study of the universe, and how it evolved.
Let me know if this helps :)
33. A student finds that the mass of 25ml of an unknown liquid is 20.5g. What is the density of this substance?
Answer:
Density, [tex]d=0.82\ g/cm^3[/tex]
Explanation:
It is given that,
Mass of an unknown liquid, m = 20.5 g
The volume of unknown liquid is 25 mL
We need to find the volume of the brass object. Mass per unit volume of an object is called its density.
We know that, 1 mL = 1 cm³
So, 25 mL = 25 cm³
[tex]d=\dfrac{m}{V}[/tex]
Putting the values, we get :
[tex]d=\dfrac{20.5\ g}{25\ cm^3}\\\\d=0.82\ g/cm^3[/tex]
So, the density of this substance is [tex]0.82\ g/cm^3[/tex]