Answer:
Mass = 0.084 g
Explanation:
Given data:
Mass of silicon = ?
Number of atoms of silicon = 1.8 × 10²¹ atom
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
1.8 × 10²¹ atom × 1 mole / 6.022 × 10²³ atoms
0.299× 10⁻² mol
0.00299 mol
Mass of silicon:
Mass = number of moles × molar mass
Mass = 0.00299 mol × 28.1 g/mol
Mass = 0.084 g
Which of the following best describes the velocity of an object?
A B0 m/s
B 30 m east
C 30 m/s east
D 30 m/s2
Answer:
[tex]\boxed {\boxed {\sf C. \ 30 \ m/s \ east}}[/tex]
Explanation:
Velocity is the vector measurement of the change in position over time. A vector measurement means the answer must include a magnitude (numerical value) and a direction.
Here are some units of velocity:
m/s (meters per second) kph (kilometers per hour) km/s (kilometers per second)There are many other units, but m/s is the most common.
We can eliminate choice B and D, because the units (meters-m and meters per second squared-m/s²) are not for velocity.
We are left with choice A (30 m/s) and C (30 m/s east). Remember, velocity needs a number and a direction. C contains the direction east, so it must be the correct answer.
12.3 moles of sodium is what mass of Na?
Answer:
1 mole of Na = mass of 22.99 g, 1 mole of Si = mass of 28.09 g.
4. (10 Points) Write a single replacement reaction where one of the reactants is
ammonium nitrate.
Include the states of matter for each of the reactants and products.
Answer:
For each balanced reaction, indicate the total number of atoms in the table below. Reaction. Total Number of Atoms. Reactant Side 1 Product Side. (Left).
Explanation:
Which substance is correctly identified as a homogeneous or heterogeneous mixture?
A. salad -- heterogeneous
B. milk --- heterogeneous
C. river water --- homogeneous
D. beach sand --- homogeneous
Answer:
A
Explanation:
A salad with lettuce, cheese, seeds, tomatoes, broccoli, and other vegetables is an example of a heterogeneous mixture.
Milk is not mixed with anything so that is incorrect
River water is mixed in with dirt and minerals so this one is incorrect
Beach sand is incorrect because you can see colored particles.
A molecule contains 24.36 g of nitrogen and 62.64g of sliver
Answer:
This molecule is AgN3
Explanation:
Answer:
AgN3
Explanation:
Mass of nitrogen N is given as 24.36 g
Molar mass of nitrogen N= 14 g/mol.
amount of substance in mol of N = mass/molar mass
=24.36 g/ 14 g/mol.
=1.74 mol.
Given mass of silver= 62,64 g.
Molar mass of silver Ag=107.87 g/mol
Number of mols=62.64 g ÷ 107.87 g/mol.
=0.58 mol.
Ratio of number of mol of N and number of mols of Ag = 1.74 mol / 0.58 mol
=3:1
Hence, empirical formula is AgN₃.
During a chemical or physical change, energy may be...
a. created into another form
b. destroyed and reinvented into another form
c. converted into another form
d. disappeared
Answer: C: Converted into another form
Explanation: pues es esa calale y si va a hacer
During a chemical or physical change, energy is converted to another form. Energy cannot be created or destroyed. During a chemical reaction, physical change the energy and mass are conserved.
What is law of conservation of energy ?According to the law of conservation of energy energy can neither be crated nor be destroyed. Hence, the total energy of a system is always conserved.
However, energy can be transformed from one form to the other. Therefore, the energy lost in one form is gained in another form. For example, in all electrical devices, the electrical energy is converting to other forms of energy such as light, thermal , mechanical etc.
Similarly, during a chemical reaction, the energy released by a reaction system is equal to the energy absorbed by other reacting system. Similarly in electrochemical cells the chemical energy is converting to electrical energy.
Find more on energy transformation:
https://brainly.com/question/17589256
#SPJ6
What is the rise in sea level between 1930 and 2003?
A)
About 20cm
B)
About 16cm
C
About 12cm
Answer:
about 16
Explanation:
its 20 - ( approximately 5)
= approximately 16
Answer:
It should be (C) about 12cm
SOMEONE HELP ME PLEASE!!! ILL GIVE BRAINLY
Physical properties behave identically for all matter under the same conditions.
Physical properties cause atoms and molecules to change structure when substances are mixed.
Physical properties can be observed without changing the identity of a substance.
Physical properties are observed by seeing how a substance reacts with other substances.
Answer:
the answer is c
Explanation:
My reasoning is that its most likely
Methane(CH4) is a gas at room temperature, Methanol (CH3OH) is a liquid. Explain why using types of intermolecular forces present.
Explanation:
Methane is a gas at room temperature but methanol is a liquid because in methane there's London dispersion intermolecular force but in methanol there's H-bond and London dispersion force. H-bond is more stronger than London dispersion force. So, it increases the boiling point of methanol that's why methane is gas at room temperature due to weak attraction of London dispersion force and methanol is liquid.
Methanol has a higher boiling point than methane due to stronger intermolecular forces (IMFs), or attraction between individual molecules. This makes its molecules more difficult to separate, requiring more energy and resulting in a higher boiling point.
What are intermolecular forces?An intermolecular force is a force that mediates the interaction of molecules, including electromagnetic forces of attraction or repulsion that act between atoms and other types of neighboring particles, such as atoms or ions.
Intermolecular forces are classified into five types namely,
Ion-dipole forces.Ion-induced dipole forces.Dipole-dipole forces.Dipole-induced dipole forces.Induced dipole forces.Between ions and polar dipole molecules, ion-dipole forces exist.
Since of stronger intermolecular forces (IMFs), or attraction between individual molecules, methanol has a higher boiling point than methane.
This makes it more difficult to separate its molecules, requiring more energy and resulting in a higher boiling point.
Thus, this is the reason of using types of intermolecular forces present.
For more details regarding intermolecular forces, visit:
https://brainly.com/question/9007693
#SPJ2
As shown by the periodic table, why do the elements potassium and sodium have similar chemical properties?
Are scientist improving the plant or corrupting it
Answer:
46 percent of trees have been cut down.
Scienctists helps plants, but humans do destroy a lot of plants.
Scientists - helps increase plant growth.
Woodchoppers - helps decrease plant growth.
HELP IN 8TH GRADE ADV SCIENCE
Answer:
protons: 36
neutrons: 48
electrons: 36
how is wind energy captured?
where is wind energy found?
how is water energy captured?
where is water energy found?
plz use the passage i put. plz and thank you!!!!!
What is it called when elements combine to form a chemical compound?
Explanation:
A compound is a unique substance that forms when two or more elements combine chemically.Compounds form as a result of chemical reactions. The elements in compounds are held together by chemical bonds. A chemical bond is a force of attraction between atoms or ions that share or transfer valence electrons.hope it helpful ✌️✌️
what's the molar mass of Li3p
Answer:
51.79g Li₃P.
Explanation:
Li has a molar mass of 6.94 g (since there are 3, you multiply it 3 times) and P has a molar mass of 30.97 g. 6.94(3) + 30.97 = 51.79g.
2CuO+2NH3------ 3Cu + 3H2O+ N2. Given that the relative molecular mass of copper oxide is 80, what volume of ammonia is required to completely reduce 120 g of Copper oxide? ( Cu=64, O=16, N=14)
Volume of Ammonia(NH₃) = 22.4 L
Further explanationGiven
Reaction
3CuO+2NH₃⇒ 3Cu + 3H₂O+ N₂
In the problem, the CuO coefficient should be 3 not 2
M CuO = 80
mass CuO = 120 g
Required
The volume of NH₃
Solution
mol CuO :
[tex]\tt mol=\dfrac{mass}{M}\\\\mol=\frac{120}{80}\\\\mol=1.5[/tex]
From the equation, mol ratio CuO : NH₃ = 3 : 2, so mol NH₃=
[tex]\tt \dfrac{2}{3}\times 1.5=1~mol[/tex]
Assume at STP(0 °C, 1 atm) ⇒1 mol = 22.4 L, then volume of NH₃=22.4 L
Which of these are an atom's valence electrons?
Answer:
The Outer-most Electron shell contains the valence electrons.
Bonus Info:
Valence Electrons are used by atoms to make ionic bonds.
Answer:
Valence electrons are the electrons in the outermost shell, or energy level, of an atom. For example, oxygen has six valence electrons, two in the 2s subshell and four in the 2p subshell. We can write the configuration of oxygen's valence electrons as 2s²2p⁴.
Explanation:
ur welcome
i was doing this in school and i watched a video
What is the name given to the group 0 elements
Answer:
the noble gases
What is this called? it might be sideways but it show look like a Y
Answer:
I'm thinking it might be Element 39: Yttrium, as this is Chemistry.
Explanation:
PLEASE HELP !!
Use the diagram below to answer the following questions.
PLEASE HELP
E TE
Figure B
In Figure B, which region contains the noble gas family of elements?
ОА
OD
ОС
OB
Noble gas located in the region D
Further explanationNoble gas are located in group 18 in the periodic table consisting of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), have a stable electron configuration where the valence electrons are 8(full outer shell of electrons), so it is very hard to react because of its stability
If we look at the periodic system of the elements, the noble gases are on the far right, so that in Figure 8 it is located in area D
And the other region :
A : alkali elements(group 1),
B : alkaline earth elements(group 2)
C : halogen elements(group 17)
Two substances in a mixture differ in density and particle size. theses properties can be used to
Answer:
option 1. Two substances in a mixture differ in density and particle size. These properties can be used to separate the substances. These properties can be manipulated in order to have a better separation between the two substances.
Explanation:
Answer:
Two substances in a mixture differ in density and particle size. These properties can be used to separate both of them using the separating funnel or using filtration (filter paper).
Explanation:
Since their densities are different, one substance should float above the other in the mixture which allows for the separating funnel to let the substance sinking below (with the heavier density) to flow out first before changing the beaker to let the lighter substance flow out.
The substance with a bigger particle size would not be able to pass through the filter paper unlike the substance with the smaller particle size as the filter paper's pores is not big enough for it to pass through, separating both substances (with one on the paper and the other outside the filter paper, preferably in the beaker placed below the paper).
The __________ system is responsible for bringing oxygen into the lungs and releasing carbon dioxide from the body
Answer:￣ﾉﾞ(｡･∀･)ﾉﾞo(*￣▽￣*)ブ(*￣3￣)╭o(*￣▽￣*)ブ(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭•)>⌐)↖↗↘↙↜↚↯↟↝↖↔↕↙↘↙↘↘↞↴↯↚↨⇌⇋⇆⇉⇑↶⇋⇋↳¾⁷¼¼⁶⁴⁷⁰⁰⁰⁹⅕⅘⅓⅕⅓⅕⨊⨡⨔⨩⨦⨶⨼⨿⨷⨷⨻⨼⨹₴ The answer is resperitory
Explanation:
When we drink water, it is absorbed into our blood through the digestive tract. If the concentration of water in body cells is low, cells must get water from the blood. What process allows water to enter body cells from the blood?
Answer:
Osmosis
Explanation:
Water is very essential for the body. When we drink water, our blood cells absorbs water from the body. This happen by a process called as osmosis process. Osmosis is type of diffusion process.
Water along with oxygen and carbon dioxide are some of the simple molecules that moves into the blood cell. Osmosis is the process by which water molecules passes into the cell bodies through its semi permeable membrane.
When using a light microscope, focus the specimen with the scanning objective
lens first.
Reasoning:
Answer:
The light microscope bends a beam of light at the specimen using a series of lenses to provide a clear image of the specimen to the observer.
What is environment?
Answer:
where an organism lives which includes everything that surrounds and influences the organism.
What would happen if a neutron was added to Lithium (7)
Answer:
if you add a neutron to lithium-7 it becomes a compound nucleus of lithium-8
What is the molecular formula of the molecule that has an empirical formula of CH2O and a molar mass of 120.12 g/mol
Answer:
C4H8O4
Explanation:
Let (CH20)x
C=1*12.01=12.01 (12.01, 1.01, 16.00 Avg mass of elements)
H=2*1.01=2.01
O=1*16.00=16.00
12.01 + 2.01 + 16.00 = 30.03
120.12/30,03=4
==> (CH2O)4 = C4H8O4
The molecular formula of the molecule that has an empirical formula of [tex]CH_2O[/tex] is equal to [tex]C_4H_8O_4[/tex].
Given the following data:
Empirical formula = [tex]CH_2O[/tex]Molar mass = 120.12 g/mol.Scientific data:
Molar mass of oxygen = 16 g/mol.Molar mass of hydrogen = 1 g/mol.Molar mass of carbon = 12 g/mol.To determine the molecular formula of the molecule that has an empirical formula of [tex]CH_2O[/tex]:
First of all, we would find the molar mass of [tex]CH_2O[/tex]:
[tex]CH_2O =12 +(1\times2)+16\\\\CH_2O =30\;g/mol[/tex]
For molecular formula:
[tex](CH_2O)n = 120.12\\\\30n = 120.12\\\\n=\frac{120.12}{30}[/tex]
n = 4.0
[tex](CH_2O)_4 = C_4H_8O_4[/tex]
Read more: https://brainly.com/question/21280037
What is the molar mass of phosphorus pentachloride and uranium hexafluoride?
Answer:
PCl₅ = 208.22g/mol. UF₆ = 352.03g/mol.
Explanation:
Find the atomic mass of each element–and if there's a subscript (you multiply the atomic mass by that much). P= 30.97g, Cl= 35.45g; 30.97+35.45(5) = 208.22g [same idea with UF₆]
i need to know what occupied vs full means for chemistry
SOMEONE HELP ME PLEASE ILL GIVE BRAINLY