Plz help! :D
What element is as hard as magnesium?
Answer:
calcium
Explanation:
The sun is shining today,
O qualitative
quantitative
Answer: Qualitative
Explanation: It isn't talking about the amount, it is talking about the quality so it would be qualitative and not quantitative.
As part of a chemistry experiment, Sam notes that the temperature at which liquid mercury
freezes into a solid is -102 Fahrenheit (F). The beaker of liquid mercury provided to him Is
at a room temperature of 68". By how many degrees will Sam have to cool the liquid
mercury for it to freeze into a solid?
-102"F
-34°F
102°F
170°F
o
Answer:
-34¨F
Explanation:
Multiple choice!
:D god
of the first 103 elements, how many have just ine letter in their symbol
Answer:
14 elements.
Explanation:
B
boron
C
carbon
F
fluorine
H
hydrogen
I
iodine
N
nitrogen
O
oxygen
P
phosphorus
K
potassium
S
sulfur
W
tungsten
U
uranium
V
vanadium
Y
yttrium
An
is made
up of one or more of the same kind of atom
chemically combined.
atom
element
molecule
compound
Answer:
The answer of this question is molecule
How many moles are in 5.25 X 10 25
atoms of Au?
Answer:
The answer is 87.21 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\ [/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{5.25 \times {10}^{25} }{6.02 \times {10}^{23} } \\ = 87.2093023...[/tex]
We have the final answer as
87.21 molesHope this helps you
At which temperature would air hold the LEAST water vapor?
A. 13°C (55°F)
B. 35°C (95°F)
C. 24°C (75°F)
D. 2°C (36°F)
Answer:
2°C
Explanation:
The answer is D because cooler air holds less water vapor than warmer air, and 2°C is the coldest choice, so there's your answer!
At 2°C (36°F) temperature would air hold the LEAST water vapour. Hence, option D is correct.
What is temperature?Temperature expresses hotness and coldness or a measure of the average kinetic energy of the atoms or molecules in the system.
At 2°C (36°F) temperature would air hold the LEAST water vapour because cooler air holds less water vapour than warmer air, and 2°C is the coldest choice.
Hence, option D is correct.
Learn more about temperature here:
brainly.com/question/28004147
#SPJ5
Write the chemical formula for the following: magnesium iodide
Answer:
Mgl2 is your answer. Can I get brainliest
Which type of reaction is Mg + S → MgS?
polymerization
synthesis
replacement
decomposition
The type of reaction is Mg + S → MgS is of synthesis reaction. Therefore, the correct option is option B among all the given options.
What is synthesis reaction?A synthesis reaction occurs when multiple chemical species unite to create a more complex product. One of the most typical chemical reactions, it is also known as a direct reaction.
A bigger compound is created when two or maybe more reactants mix. A deconstruction reaction, which occurs when the bonds in a complex product are broken and it separates the product in with its individual components or elements, is the reverse of a synthesis process. The type of reaction is Mg + S → MgS is of synthesis reaction.
Therefore, the correct option is option B among all the given options.
To know more about synthesis reaction, here:
https://brainly.com/question/16987748
#SPJ7
How is heat transferred when you touch an ice cube?
Answer:
The heat is transferred from your hand to the ice, this is because, as we know, heat gets transferred from a hot object to a colder object.
In this case, our hand is clearly hotter than the ice cube.
Therefore, the heat is transferred from your hand to the ice cube.
If my answer helped, kindly mark me as the brainliest!!
Thank You!!
3. describe how unequal heating causes weather
Answer:
The uneven heating causes temperature differences, which in turn cause air currents (wind) to develop, which then move heat from where there is more heat (higher temperatures) to where there is less heat (lower temperatures).
Explanation:
Which molecules of the following gases will
have the greatest average kinetic energy?
1. N2 at 1 atm and 298 K
2. CO2 at 1 atm and 298 K
3. H2 at 0.5 atm and 298 K
4. He at 0.1 atm and 298 K
5. All of the molecules have the same kinetic
energy
Answer:
.
Answer: 5 All of the molecules have the same kinetic energy
since the temperature is kept constant at 298 K
Explanation:
The AVERAGE kinetic energy is directly proportional to the absolute temperature.
All the molecules have the same average kinetic energy as average kinetic energy is directly proportional to the absolute temperature. So, the correct option is 5.
What is average kinetic energy?
The average kinetic energy (K) is equal to one-half of the mass (m) of each gas molecule times the root mean square speed (Vrms) squared.
We know that the average kinetic energy is directly proportional to the absolute temperature.
All of the molecules have the same kinetic energy since the temperature is kept constant at 298 K.
Therefore, All the molecules have the same average kinetic energy as average kinetic energy is directly proportional to the absolute temperature.
To learn more about average kinetic energy, click here:
https://brainly.com/question/24134093
What happens to the heat energy that leaves the milk?
Answer:
it gets cold or warm
Explanation:
pleas get me 53 likes
If the density of the mantle rock is about 3.3 g/cm3, then what is its specific gravity?
2.6
2.8
3.3
3.0
Answer:
2.6
Explanation:
Answer: That is wrong!!! The correct answer is C, 3.3
Explanation:
What is each quantity of the length of a pencil
Answer:
In units of measurement of length we use centimeter (cm) to measure. We can use this unit for measuring the length of a pencil, the width of a book etc. but this unit is too big to measure the thicken of a pencil. So we use another unit called millimeter (mm).
Explanation:
Why is it easy for some elements to lose electrons and harder for others?
Answer:
The further away electrons are from the nucleus the easier it is for atoms to use electrons.
Explanation:
1Which statement about plant cells is true? A A plant cell cannot contain both a nucleus and chlorophyll. Incorrect answer B A plant cell can contain both chlorophyll and a nucleus. Incorrect answer C A plant cell must contain chlorophyll, but can have no nucleus. Incorrect answer D A plant cell has neither a nucleus nor chlorophyll.
Answer:
B A plant cell can contain both chlorophyll and a nucleus.
Explanation:
All plants are eukaryotic organisms i.e the cells of all plants possess a membrane-bound nucleus that houses their genetic material (DNA). In addition to this, most plant cells also contain a unique organelle called CHLOROPLAST, which they use to capture the energy from sunlight in order to perform a process called PHOTOSYNTHESIS.
According to this question, plant cells can contain both chlorophyll and a nucleus. They can possess chlorophyll because chlorophyll is a pigment in their chloroplast that captures the light energy.
Blue bowling ball rolled with a force of 15 N accelerates at a rate of 3 m/sec2 a second red ball rolled with the same force accelerates at 4 m/sec2. What are the masses of the two balls?
Answer:
1. Mass of the blue ball is 5 kg.
2. Mass of the red ball is 3.75 kg.
Explanation:
The following data were obtained from the question:
For the blue ball:
Force (F) = 15 N
Acceleration (a) = 3 m/s²
Mass (m) =.?
Force the red ball:
Force (F) = the same with that of the blue ball = 15 N
Acceleration (a) = 4 m/s²
Mass (m) =.?
1. Determination of the mass of the blue ball.
Force (F) = 15 N
Acceleration (a) = 3 m/s²
Mass (m) =.?
Force (F) = mass (m) × acceleration (a)
F = ma
15 = m × 3
Divide both side by 3
m = 15/3
m = 5 kg
Therefore, the mass of the blue ball is 5 kg
2. Determination of the mass of the red ball.
Force (F) = 15 N
Acceleration (a) = 4 m/s²
Mass (m) =.?
Force (F) = mass (m) × acceleration (a)
F = ma
15 = m × 4
Divide both side by 4
m = 15/4
m = 3.75 kg
Therefore, the mass of the blue ball is 3.75 kg
Which student was practicing poor laboratory safety?
Gunther read all the safety precautions for an experiment and collected his chemicals.
Herbert started mixing his chemicals as the teacher began explaining the lesson.
Francine washed her hands after spilling table salt on them.
Reilly tied her hair back into a ponytail after putting on her lab coat.
Answer herbert
Explanation:
cause he did not do any of the safety precautions and he was prob not listening to the teacher
where is water you can feel?
plz help me
Answer:
Ocean
Explanation:
11. Which of the following best explains why CO2 gas is easily compressible but solid
CO2 (dry ice) is incompressible?
The molecules of CO2 gas are much closer together than
the molecules in dry ice.
The molecules of CO2 gas are much smaller than the molecules
of solid CO2
O
The molecules of solid CO2 are much closer together than
the molecules of CO2 gas.
The molecules of CO2 gas attract one another, while the
molecules of the solid CO2 repel one another.
0
Answer:
The right answer is C. The molecules of solid CO2 are much closer together than the molecules of CO2 gas.
The molecules of CO2 gas are much closer together than the molecules in dry ice. So CO2 gas is easily compressible but solid CO2 is incompressible. The correct option is A.
What is dry ice?Carbon dioxide in its solid form is known as dry ice. Because CO2 does not have a liquid state at normal atmospheric pressure and sublimates directly from the solid to the gas state, it is commonly used for temporary refrigeration.
Dry ice can be a serious hazard in a small, poorly ventilated space. When dry ice melts, it emits carbon dioxide gas.
This gas can accumulate in a small space. A person can become unconscious and, in some cases, die if there is enough carbon dioxide gas present.
CO2 gas molecules are much closer together than dry ice molecules. As a result, CO2 gas is easily compressible, but solid CO2 is not.
Thus, the correct option is A.
For more details regarding dry ice, visit:
https://brainly.com/question/13972158
#SPJ2
How much heat is released by a 15-gram sample of water when it is cooled from 40.oC to 30.oC?
Answer:
Q = -627.6 J
Explanation:
Mass, m = 15 grams
Initial temperature, [tex]T_i=40^{\circ} C[/tex]
Final temperature, [tex]T_f=30^{\circ} C[/tex]
We need to find the amount of heat released by this much of sample of water. We know that heat released is given by the below formula :
[tex]Q=mc\Delta T[/tex]
c is specific heat of water, [tex]c=4.184\ J/g-K[/tex]
[tex]\Delta T=T_f-T_i\\\\=(30^{\circ}-40^{\circ} )\ C\\\\=-10^{\circ} C\\\\=-10\ K[/tex]
So,
[tex]Q=15\times 4.184\times -10\\\\Q=-627.6\ J[/tex]
Hence, 627.6 J of heat is released and negative sign shows that energy is being given off.
in a complete paragraph (5+ sentences) rank the strength of attraction between the protons and valence electrons of atoms of Nitrogen, Gallium, and Arsenic. Fully EXPLAIN why you ranked them in the way you did, comparing and explaining the differences in their Coulombic attraction as you learned yesterday.
Answer:
N> As> Ga
Explanation:
There are two important factors that come into play when we are discussing the strength of attraction between protons and valence electrons;
1) distance of the valence electrons from the nucleus
2) size of the nuclear charge
If we consider the elements; nitrogen, arsenic and gallium, nitrogen is in period 2. This implies that it has only two shells. The valence electrons are closer to the nucleus and are more strongly attracted to the protons in the nucleus.
Arsenic and gallium are both in period 4. This implies that they both contain a total of 4 electron shells. However, arsenic has a nuclear charge of 33 protons while gallium has a nuclear charge of 31 protons. Hence arsenic has a greater size of nuclear charge than gallium. The attraction between protons and valence electrons in arsenic is therefore greater than it is in gallium.
Which of the following is an irreversible physical change?
a) melting a piece of lead
b) sharpening a pencil
c) dissolving sugar into water
d) boiling water
Answer:
b) sharpening a pencil
Explanation:
If you melt lead, boil water, or dissolve sugar in water, you can return all of them back to their original state. If you sharpen a pencil, you can't reattach the shavings as they were originally.
You may put all of them back to their original states by melting lead, heating water to a boil, or dissolving sugar in water. You cannot rejoin the shavings from a sharpened pencil in their original position. Thus, option B is correct.
What is irreversible physical change?When something changes physically but not chemically, it has undergone an irreversible physical alteration that cannot be reversed.
Sharpening a pencil is a perfect example of an irreversible physical change. The wood turns to dust when you sharpen it. Just in a different shape, it is still wood. That wood dust cannot be transformed back into a pencil.
You cannot put a piece of paper back together the same way it was before you tore it if you tear it into tiny pieces.
An irreversible alteration is one that cannot be undone or that cannot be returned to its original state, such as when milk turns into curd, iron turns rusty, paper burns, food is cooked, etc.
Therefore, sharpening a pencil is an irreversible physical change
Learn more about irreversible here:
https://brainly.com/question/24111037
#SPJ2
If there was an airplane that went 2,000 miles in 3.5 hours. Find the average speed
Answer:
The answer is 571.43 mi/hrExplanation:
The average speed in the question can be found by using the formula
[tex]v = \frac{d}{t} \\ [/tex]
where
d is the distance
t is the time taken
We have
[tex]v = \frac{2000}{3.5} \\ = 571.428571...[/tex]
We have the final answer as
571.43 mi/hrHope this helps you
If air temperature decreases, then
wave height will decrease
ocean temperature will also decrease the same amount
ocean temperature will also decrease, but not as much
ocean temperature will also decrease, but a greater amount
wave height will increase
Answer:
ocean temp
Explanation:
If air temperature decreases, then wave height will decrease and ocean temperature will also decrease, but not as much.
What is ocean temperature ?The water's temperature at the surface is known as the ocean surface temperature. Depending on the measuring technique, the term "surface" might signify anything from 1 millimeter to 20 meters below the sea's surface.
Due to changes in solar radiation and the physical characteristics of water, the temperature of ocean water fluctuates depending on location, both in terms of latitude and depth.
Water contracts and gets denser as it cools. The density of water is influenced by temperature and salinity, and as a result, water moves up or down through the ocean's strata and circulates as currents.
Thus, option B is correct.
To learn more about ocean temperature, follow the link;
https://brainly.com/question/12111508
#SPJ2
I'm not sure what to do here...
Answer:
Explanation:
As relative molecular mass of molecule increases its rate of diffusion decreases . Mr of HCl is 1+35.5=36.5 which is greater than Mr of NH3 which is only 14+3=17. As HCl is heavier it'll diffuse at a lower rate so travel less distance whilst NH3 will cross a greater distance as it diffuses faster so white solid appears closer to HCl that is approximately B.
define atom and give an example
Answer:
Many atoms consist of a positively charged nucleus composed of protons and neutrons surrounded by a negatively charged cloud of electrons. At its most basic level, an atom is any particle of matter that contains at least one proton. ... Here are some examples of atoms: Neon (Ne) Hydrogen (H)
Explanation:
Plastic, rocks, rabbits and steel are all made of matter. Matter is made up of tiny particles called ________.
Question 1 options:
a nucleus
atoms
energy
molecules
Answer:
atoms should be the correct answer
Answer:
Matter is made up of tiny particles called atoms.
Explanation:
Atoms are made up of protons, neutrons and electrons. Atoms come together to form molecules which are building blocks for all types of matter.