Answer:carbon-14 levels in the atmosphere
Explanation:
When carrying out radiocarbon dating, the level of carbon-14 in a sample is compared with the level of carbon 14 in the atmosphere because, objects exchange carbon-14 with the atmosphere.
Comparison of the activities of carbon-14 in the atmosphere and in the sample gives the age of the sample since the half-life of carbon-14 is a constant.
Nio conducts a science experiment. He puts yeast into a bottle with water and sugar, and then caps the bottle with a balloon. He returns two hours later and notices there are bubbles on the surface of the mixture in the bottle and that the balloon has inflated, but there are no other apparent changes.
What most likely happened?
a non-chemical change, because there are no indicators of chemical changes taking place
a chemical change, because the mixture changed color
a chemical change, because a gas was produced
a non-chemical change, because the changes that occurred are reversible
Answer:the answer is a chemical change, because a gas was produced
Explanation: yeast is a chemical
Answer:
The answer is C.
"Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions."
Explanation:
What are two properties of most nonmetals
Answer: Summary of Common Properties
High ionization energies.High electronegativities.Poor thermal conductors.Poor electrical conductors.Brittle solids—not malleable or ductile.Little or no metallic luster.Gain electrons easily.Dull, not metallic-shiny, although they may be colorful.Explanation:
May I please have brainiest?
Answer:
The two properties of most non metals are high ionization energy and poor electrical conductivity. The correct option among all the options that are given in the question is option "1". In general it is known that nonmetals are very poor conductors of heat and electricity. The nonmetals that are solid are normally very brittle and has very little or no metallic luster at all. Nonmetals are highly reactive and show variety of chemical properties. It can also be pointed out that the nonmetals gain electrons very easily.
brainliest pleaseee :)
A runner completes a 400m race in 43.9s. What is his average speed?
Answer:
average speed around 9.1 meters/second
Explanation:
400 divided by 43.9
A hypothetical element has two main isotopes with mass numbers of 59 and 62. If 73.00% of the isotopes have a mass number of 59 amu, what atomic weight should be listed on the periodic table for this element? Answer in units of amu.
since 73% of the isotope is given, take 100%-73% to get the remaining % of the isotopes which is going to be 27%.
hence,
atomic weight= (73×59) + (27×62)
=4307+1302
=5609 amu
Which of the following happens to the particles when the temperature of liquid water drops?
Explanation:
when water is in liquid form and the temperature DROPS it becomes solid ice the process is melting , freezing and evaporation this goes in a circle
What is your carbon footprint?
the amount of carbon dioxide you use when recycling
the amount of oxygen put into the atmosphere due to your consumption of fossil fuels
the amount of carbon dioxide and oxygen in the atmosphere at any given time
the amount of carbon dioxide put into the atmosphere due to your consumption of fossil fuels
Answer:
c. .....................
Answer: the amount of carbon dioxide put into the atmosphere due to your consumption of fossil fuels
Your carbon footprint is the amount of carbon dioxide and other carbon compounds emitted, because of your use of fossil fuels.
Hope this helps!
What is the volume of a weather balloon that has 39 grams of helium with a density 0.017 g/mL?
Answer:
The answer is 235.29 mLExplanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\ [/tex]
From the question.
density = 0.017 g/mL
mass = 4 g
We have
[tex]volume = \frac{4}{0.017} \\ = 235.2941176...[/tex]
We have the final answer as
235.29 mLHope this helps you
All surfaces have texture, which means it affects how things move over it. When it takes a long time for friction to slow down an object, what is most likely true about the surface the object is moving on? The surface is dry. The surface is rough. The surface is uneven. The surface is smooth.
The question is incomplete, the complete question is;
All surfaces have texture, which means it affects how things move over it. When it takes a long time for friction to slow down and object, what is MOST LIKELY true about the surface the object is moving on? (A) The surface is dry (B) The surface is rough (C) The surface is uneven (D) The surface is smooth
Answer:
(D) The surface is smooth
Explanation:
Friction exists because of relative motion between two surfaces in contact with each other. However the magnitude of friction depends on how rough or smooth the surface is.
For smooth surfaces, there is little or no resistance to motion as objects move over the surface. Hence objects take a longer time to slow down on a smooth surface due to very little friction.
On a rough surface, objects tend to slow down relatively quickly. Hence, less resistance to motion on a smooth surface makes an object to take a longer time to slow down on a smooth surface than on a rough surface.
Answer: D
Explanation: Because if the surface is smooth it causes it to be more even for it to be able to cause Friction
if you find this helpful, Your welcome, if not, sorry.
4. Advection fog forms when warm moist air comes in from the Pacific Ocean and
blows over the cold California current.
A.True
B.False
Answer:
A, True
Explanation:
Which of the following atoms has the greatest ionization energy?
a.)W
b.)C
C.)d
P.)d
Answer:
helium
Explanation:
because there are no electrons screening it from the nucleus
You just got a free ticket for a boat ride, and you can bring along
2 friends! Unfortunately, you have 5 friends who want to come along.
Answer:
10
Explanation:
Khan Academy
Each water molecule can form hydrogen bonds with up to _____ neighbors
Group of answer choices
6
8
2
4
Answer:
2
Explanation:
thats the answer.have good day
Write the principle of separation of mixture.
Explanation:
Mixtures can be separated using a variety of techniques. Chromatography involves solvent separation on a solid medium. Distillation takes advantage of differences in boiling points. Evaporation removes a liquid from a solution to leave a solid material.
Answer question number 3
A piece of gold has a mass of 21.7 kg and a volume of 5.78 cm3 . What is the density of gold? (Convert kgg)
Answer:
The answer is 3754.33 g/cm³Explanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question
mass = 21.7 kg = 21700 g
volume = 5.78 cm³
We have
[tex]density = \frac{21700}{5.78} \\ = 3754.3252...[/tex]
We have the final answer as
3754.33 g/cm³Hope this helps you
Which of the following elements has the largest electronegativity? A) Bismuth B) Nitrogen C) Potassium D) Arsenic
Calculate the average atomic mass of unknown element X. You determine that isotope 127X makes up 80%, isotope 126X makes up 17%, and isotope 128X makes up 3%.
A. 127.10 amu
B. 126.86 amu
C. 127.54 amu
D. 126.20 amu
Answer:
Option B. 126.68 amu
Explanation:
The following data were obtained from the question:
Isotope A (¹²⁷X):
Mass of A = 127
Abundance (A%) = 80%
Isotope B (¹²⁶X):
Mass of B = 126
Abundance (B%) = 17%
Isotope C (¹²⁸X):
Mass of C = 128
Abundance (C%) = 3%
Average atomic mass of element X =.?
Th4 average atomic mass of X can be obtained as follow:
Average atomic mass = [(Mass of A × A%)/100] + [(Mass of B × B%)/100] + [(Mass of C × C%)/100]
= [(127 × 80)/100] + [(126 × 17)/100] + [(128 × 3)/100]
= 101.6 + 21.42 + 3.84
= 126.68 amu
Therefore, the average atomic mass of X is 126.68 amu
Two liters of hydrogen gas are stored at a
pressure of 100 kPa. If the temperature
does not change, what will the volume
of the gas be when the pressure is
decreased to 25 kPa?
Answer:
the volume will expand
Explanation:
gas under pressure contracts, and expands with a lesser pressure
The volume of the hydrogen gas at 25 kPa is 8 Liters.
Explanation:
Given:
At constant temperature, 2 liters of hydrogen gas at 100kPa pressure.
To find:
The volume of the hydrogen gas at 25kPa.
Solution:
The initial pressure of the hydrogen gas =[tex]P_1=100 kPa[/tex]
The initial volume of the hydrogen gas at 100 kPa =[tex]V_1=2 L[/tex]
The final pressure of the hydrogen gas =[tex]P_2=25 kPa[/tex]
The final volume of the hydrogen gas at 25kPa = [tex]V_2=?[/tex]
Using Boyles law:
[tex]P_1V_1=P_2V_2\\100kPa\times 2 L=25 kPa\times V_2\\V_2=\frac{100 kPa\times 2L}{25 kPa}=8L[/tex]
The volume of the hydrogen gas at 25 kPa is 8 Liters.
Learn more about Boyles law here:
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1. The human eye can detect wavelengths of light as short as 0.000037 cm. What is this
wavelength in nanometers?
Answer:
0.000037 cm is 370 nanometers
Explanation:
what is potiential and kinetic engergy? pls someone answer my question
Answer:
Potential Energy is stored energy or energy of position (gravitational). The object isn't moving. For example, a ball being held is potential energy because the object isn't moving but it has the potential of turning into kinetic energy.
Kinetic Energy is the energy of motion. For example, running. You are moving, and there is clear action and activity
Energy stored in an object due to its position is Potiential energy . Energy that is moving object has due to its motion is Kinetic energy .
Determine the mass of 31.4 moles of Sodium.
Answer:
721.9 grams
I hope this helps!
Plz help! :) :D I will mark you as BRAINLIEST for the best answer!!! ( I actually mean it)
Physical and Chemical Properties of Magnesium
Here is an EXAMPLE of how it has to be like. Instead of Mercury, you HAVE to do Magnesium
Physical Properties of Mercury: ”I’m a highly stable element, so you can count on me”
Chemical Properties of Mercury: ”I love to travel but I do corrode aluminum so we won’t be flying off on adventures in airplanes planes anytime soon”
Which statement best defines potential enregy?
A. Potential energy is stored energy.
B. Potential energy is energy that can change over time.
C.Potential energy is the energy of motion.
D. Potential energy is the type of energy a roller coaster uses.
Answer:
A. Potential energy is stored energy
Explanation:
Answer:
A
Explanation:
i have the same question
which balances the equation Mg + O2 → MgO
Answer:
2Mg+[tex]O_{2}[/tex]→2MgO
Explanation:
The first step is magnesium + oxygen equals magnesium oxide
The second step is changing that into an equation which looks like Mg+[tex]O_{2}[/tex]→MgO
The third step is to 2*Mg and 2*O as well as the product has to be 2*Mg,2*O which gets the equation to become balanced as 2Mg+[tex]O_{2}[/tex]→2MgO
The coefficient 2 balance the given reaction. The balanced equation for the given reaction is given as [tex]\rm Mg + O_2 \rightarrow 2MgO[/tex].
A balanced equation is a mathematical representation of a chemical reaction that respects the law of mass conservation. It depicts the reactants and products of the reaction, as well as the relative amounts of each species. The unbalanced equation is [tex]\rm Mg + O_2 \rightarrow MgO[/tex]. One magnesium (Mg) atom on the left side and one on the right side, so the magnesium is already balanced. Balance the oxygen (O) atoms. On the left side, there are two oxygen (O) atoms present in the O2 molecule. On the right side, there is only one oxygen (O) atom in the MgO molecule. To balance the oxygen atoms, we need to add a coefficient of 2 in front of MgO: [tex]\rm Mg + O_2 \rightarrow 2MgO[/tex]. The balanced equation is [tex]\rm Mg + O_2 \rightarrow 2MgO[/tex].
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I need help on Chemistry?
ANYONE PLEASE?
Answer:
1. 1g/ml
Explanation:
1. Density is mass divided by volume (g/mL).
10g/10mL = 1 g/mL
2. When you already know the density and the volume, you can use the density as a unit converter.
[tex]5mL*\frac{20g}{mL} = 100g[/tex]
3. It's the same with density and mass.
[tex]20g*\frac{1mL}{5g} = 4mL[/tex]
A piece of wood that measures 2.7 cm x 5.5 cm x 3.9 cm has a mass of 84 g what is the density of the wood
The density of the wood : 1.45 g/cm³
Further explanationDensity is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
With the same mass, the volume of objects that have a high density will be smaller than objects with a smaller type of density
The unit of density can be expressed in g/cm³ or kg/m³
Density formula:
[tex]\large {\boxed {\bold {\rho ~ = ~ \frac {m} {V}}}}[/tex]
ρ = density
m = mass
v = volume
Volume of the wood[tex]\tt V=2.7\times 5.5\times 3.9=57.915~cm^3[/tex]
density[tex]\tt \rho=\dfrac{m}{V}\\\\\rho=\dfrac{84~g}{57.915~cm^3}=\boxed{\bold{1.45`g/cm^3}}[/tex]
Why can two water molecules stick to each other?
A foam square has a mass of 25 g and a volume of 90 mL. What is the density?
Answer:
The answer is 0.28 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
So we have
[tex]density = \frac{25}{90} = \frac{5}{18} \\ = 0.277777...[/tex]
We have the final answer as
0.28 g/mLHope this helps you
Joe bought a roll of gray duct tape containing 5400 inches. If there are 5280 feet in a mile, how
many miles long is Joe's roll of duct tape?
Answer:
STANDARD: 0.085 mi, 450 ft, or 150 yds
METRIC: 0.137 km, 137.16 m, or 13716 cm
Explanation:
How long will it take for 500.0g of radium decay to 2.0g