Which of the following substances is an element? A. water B. table salt C. iron oxide D. hydrogen
Answer:
[tex]\boxed {\tt D. \ Hydrogen}[/tex]
Explanation:
An element has a uniform composition, cannot be broken down by chemical change, every atom has the same atomic number, and can be found on the Periodic Table.
Water is made of hydrogen and oxygen atoms (H₂O) so it is not an element.
Table salt is made of sodium and chloride atoms (NaCl) so it is not an element.
Iron oxide is made up of iron and oxygen atoms, so it is not an element.
Hydrogen is an element. It can be found on the Periodic Table as element H.
The correct answer is D. Hydrogen
Is Magnesium less reactive than Aluminum ? Yes or No
Answer:
The answer is no
Answer:
yes
Explanation:
some metals are reactive than others. Example: (a) Magnesium is more reactive than silver. (b) Magnesium reacts with oxygen but silver doesn't because magnesium is more reactive than silver.
please mark me brainliest hope this helps! god bless
Fill in the blank to the Periodic Pun
Oh, I ate too much! Now I’m going to _________________ the rest of the night.
Answer:
stay up?...or shxt the rest of the night
Answer:
Answer C
Explanation:
14.600 oz = ____g
(HELP ME PLEASE)
Answer:
The answer is 414.64 g the other answer is wrong
Explanation:
I took this assignment and got this question right
A student has a sample of solid calcium. It is shiny and metallic looking. He squeezes a pipet of concentrated sulfuric acid onto the calcium. Bubbles are produced and the calcium appears to disappear. The test tube gets hot. What kind of change occurred?
Answer:
Physical change
Explanation:
There are two types of changes: physical change and chemical change. Physical change is defined as the change that changes the physical appearance of the substance and do not affcet the chemical composition of the substance whereas chemical change causes changes in the chemical composition of the susbstance.
The given example shows physical change because solid calcium undergoes sublimation. process in which a solid substance changes into gaseous phase directly without undergoing liquid phase.
Hence, the correct answer is "Physical change".
2. If a person in a wheelchair wanted to get to the second story of a two-story building, would it be easier to
take a short, steep ramp or a long, shallow ramp? Explain.
Answer:
The short steep ramp would be much harder because you will have to work more against gravity.
Explanation:
The long shallow ramp would be easier to take than the short, steep ramp because the person would have to use more force on the short, steep ramp to push the wheelchair against the force of gravity.
What is an inclined plane?An inclined plane or a ramp can be defined as a flat supporting surface tilted at an angle, with one end higher than the other, utilized as an aid for raising or lowering a load.
The inclined plane can be defined as one of the six classical simple machines developed by Renaissance scientists. Inclined planes can be utilized to move heavy loads over vertical obstacles.
Moving a body up an inclined plane needs less force than lifting it straight up, at a cost of an increase in the distance moved. The mechanical advantage, the factor by which the force is decreased, is equal to the ratio of the sloped surface's length to the height it spans.
The inclined plane provides the same amount of work to be done with a smaller force exerted over a greater distance. The angle of friction or the angle of repose can be defined as the maximum angle at which a load can rest motionless on an inclined plane because of the friction without sliding down.
Learn more about Inclined plane, here:
https://brainly.com/question/14983337
#SPJ2
Between Na and Na+ which has larger size
Answer:
Na+ is smaller than Na because, it has given away one electron because of which the electron shielding gets stronger due to more protons and less electrons. Whereas, Cl- is larger than Cl because it has gained an extra electron and so, the no.07/12/2010
Explanation:
0.0
A loaf of bread has a mass of
250.0 g and a volume of
2,575 cm3. What is the
density of the bread?
cm3
10
1
Answer:
0.097 g/cm3
Explanation:
divide mass over volume
Which statements describe a human-created mass extinction? Select three correct choices.
Answer:
Explanation:
where are the choices? I could help but im going to need those choices?
Sorry.
Answer:
-it results from the disappearance of entire species in a short time
-it is caused by the growth of the human population
-it is a long-term change
(A,C, & D)
Explanation:
I got the question right in Edg.
:)
How would you determine an atom's charge?
Answer:
The charge of an atom is the number of protons minus the number of electrons.
A sample of gas has a volume of 526 mL at 346 mmHg and 35.0°C. Determine the moles of gas.
Answer:
The moles of gas is 0.009474 moles.
Explanation:
Given that,
Volume = 526 mL
Pressure = 346 mmHg
Temperature = 35.0°C
We need to calculate the moles of gas
Using formula of ideal gas
[tex]n=\dfrac{PV}{RT}[/tex]
Where, P = pressure
V = volume
R = gas constant
T = temperature
Put the value into the formula
[tex]n=\dfrac{\dfrac{346}{760}\times0.526}{0.08206\times(35+273)}[/tex]
[tex]n=0.009474\ moles[/tex]
Hence, The moles of gas is 0.009474 moles.
what are parts of this water wheel system?
Answer: Explanation:
Water wheels have several important parts that work together (see diagram).
*Flowing water (delivered via a channel called a mill race)
*Large wooden or metal wheels.
*Paddles or buckets (arranged evenly around the wheel)
*Axle.
*Belts or gears.
A rectangle has a width of 7 inches height of 14 inches and a length of 12 inches find it’s volume 
Please tell me and why ?
Answer:
Thanks for the points
Explanation:
what is the orbital notation for silver?
Answer:
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d10
Explanation:
I think
What makes the atomic radius change along a period in the periodic table?
A. More electrons in the valence shell make the radius bigger.
B. More protons in the nucleus pull the electrons in, making the
atomic radius smaller.
C. The increased atomic mass makes the atomic radius bigger.
D. More electrons pair in orbitals, making the atomic radius smaller.
Answer:B
Explanation:
PLEASE APEZ HELP I DONT UNDERSTAND
A teacher placed a plastic cup of warm coffee with a lid in the freezer.
Which statement describes the frozen coffee in comparison with the warm
coffee?
A. The amount of coffee is the same.
B. The speed of the coffee molecules has increased.
C. The temperature of the coffee has increased.
D. The arrangement of the coffee molecules is the same.
Answer: The answer is A
Explanation:.
The chemical formula for hydrogen
peroxide is H2O2. What is the total
number of atoms in one molecule of
hydrogen peroxide?
A 2
B 4
C6
D 8
What mass of benzene takes
up
325 mL if its density is
0.874 g/mL?
Answer:
The answer is 284.05 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volumeFrom the question
volume = 325 mL
density = 0.874 g/mL
We have
mass = 325 × 0.874
We have the final answer as
284.05 gHope this helps you
How do clastic sedimentary rocks form?
Solid chemicals in water harden and form rocks.
Fragments of rock are squeezed and cemented together.
Lava cools and hardens into rock.
Plant and animal remains are squeezed and cemented together.
Plz help I give the brainlyest
Answer: solid chemicals in waterharden and form rocks
Explanation:
Answer:
Fragments of rock are squeezed and cemented together.
Explanation:
I took the test and got the answer below:
what are the physical characteristics of sand
Answer:
what do you mean by this ?
Explanation:
Answer:
Sand has a grainy form
Explanation: That's all I know for now
i must be present in a compound for it considered organic
Answer:
Carbon
Explanation:
Organic compounds must contain carbon. They also usually contain hydrogen, oxygen, and often nitrogen and other compounds such as phosphorus.
Nearly all organic compounds contain carbon-hydrogen bonds.
Compare and contrast Transverse Waves and Longitudinal Wave
there, so you can have choices, though they all mean the same thing.
Trillions of cells join together to form ?
Answer: you like your body and tissue and organs and stuff
Explanation: it takes so much cells because of them being so small but with out them we would not be at all the same
which type of matter cannot be broken done into simplier substances by a chemical change
Answer: Because atoms cannot be created or destroyed in a chemical reaction, elements such as phosphorus (P 4) or sulfur (S 8) cannot be broken down into simpler substances by these reactions. Example: Water decomposes into a mixture of hydrogen and oxygen when an electric current is passed through the liquid
Explanation:
Answer:
elements because they are the simplest form of matter so they can't be broken
Explanation:
Hope this helps:)
what are two things that affect gravity?
Answer:
When dealing with the force of gravity between two objects, there are only two things that are important – mass, and distance. The force of gravity depends directly upon the masses of the two objects, and inversely on the square of the distance between them.
Explanation:
Calculate the average atomic mass of silver if 13 out of 25 atoms are silver -107 and 12 out of 25 atoms are silver -109
Answer: 107.96amu
Explanation:
(107x.52)+(109x.48)
55.64+52.32=107.96
What do the elements in Group 2 have in common?
Answer:
they are all on the periodic table and they are all elements ?
Answer:
They are all alkaline each metals and they each have the same number of valence electrons
Identify arrows pointing to nonbonding electrons.
Answer:
C
Explanation:
Yessir
ASAP MULTIPLE CHOICE WILL MARK BRAINLIEST
What does Planck's equation E = h × v determine?
the number of lines on the atomic spectrum for an atom
the color of the lines on the atomic spectrum for an atom
the energy released as an electron moves to a higher orbital
the energy released as an electron moves to a lower orbital
b
the color of lines
Explanation:
on the atomic spectrum for an atom