Which unit of measurement should you use when measuring the length of an earthworm?
Answer:
kilometers.........
How many grams of potassium sulfate should be weighed to prepare 100 ppm of potassium in 250mL of solution if the purity of the salt is 98.7%?
Answer:
R=0.0564g K2SO4
When is the atomic number NOT equal to the number of electrons?
Explanation:
where there are negative or positive ions
Explanation:
Protons
Each element has an atomic number. The atomic numbers are listed along with the names and symbols of the elements on the inside cover of the text. The atomic number equals the charge on the nucleus. It therefore also equals the number of protons in the nucleus and also equals numerically the number of electrons in the neutral atom. The atomic number has the symbol Z.
Different elements have different atomic numbers; therefore, atoms of different elements contain different numbers of protons (and electrons). Oxygen has the atomic number 8; its atoms contain 8 protons and 8 electrons. Uranium has the atomic number 92; its atoms contain 92 protons and 92 electrons.
The relationship between atomic number and the number of protons or electrons can be stated as follows:
Atomic number= number of protons per atom= number of electrons per neutral atom
B. Mass Number Equals Protons plus Neutrons
Each atom also has a mass number, denoted by the symbol A. The mass number of an atom is equal to the number of protons plus the number of neutrons that it contains. In other words, the number of neutrons in any atom is its mass number minus its atomic number.
Number of neutrons = mass number - atomic number
or
Mass number = number of protons + number of neutrons
The atomic number and the mass number of an atom of an element can be shown by writing, in front of the symbol of the element, the mass number as a superscript and the atomic number as a subscript:
mass number
atomic numberSymbol of elementorA
ZX
For example, an atom of gold (symbol Au), with an atomic number 79 and mass number of 196 is denoted as:
196
79Au
C. Isotopes
Although all atoms of a given element must have the same atomic number, they need not all have the same mass number. For example, some atoms of carbon (atomic number 6) have a mass number of 12, others have a mass number of 13, and still others have a mass number of 14. These different kinds of the same element are called isotopes. Isotopes are atoms that have the same atomic number (and are therefore of the same element) but different mass numbers. The composition of atoms of the naturally occurring isotopes of carbon are shown in Table 4.2.
TABLE 4.2 The naturally occurring isotopes of carbonIsotopeProtonsElectronsNeutrons12
6C66613
6C66714
6C668
The various isotopes of an element can be designated by using superscripts and subscripts to show the mass number and the atomic number. They can also be identified by the name of the element with the mass number of the particular isotope. For example, as an alternative to
12
6C,13
6C,and14
6C
we can write carbon-12, carbon-13, and carbon-14.
About 350 isotopes occur naturally on Earth, and another 1500 have been produced artificially. The isotopes of a given element are by no means equally abundant. For example, 98.89% of all carbon occurring in nature is carbon-12, 1.11% is carbon-13, and only a trace is carbon-14. Some elements have only one naturally occurring isotope. Table 4.3 lists the naturally occurring isotopes of several common elements, along with their relative abundance.
TABLE 4.3 Relative abundance of naturally occurring isotopes of several elementsIsotopeAbundance (%)hydrogen-199.985hydrogen-20.015hydrogen-3tracecarbon-1298.89carbon-131.11carbon-14tracenitrogen-1499.63nitrogen-150.37 oxygen-1699.76oxygen-170.037oxygen-180.204IsotopeAbundance (%)silicon-2892.21silicon-294.70silicon-303.09chlorine-3575.53chlorine-3724.47phosphorus-31100iron-545.82iron-5696.66iron-572.19iron-580.33 aluminum-27100
Which best describes the purpose of a controlled experiment?
to make sure the results of the experiment support the hypothesis
to prevent a dangerous condition resulting from a reaction
to examine whether one variable causes a change in another
to prevent an undesired change in a variable
Answer: To examine whether one variable causes a change in another
Explanation:
+
Hele Oqt7nOo (Oettin
Answer:
omggggggggg that is sooo confusing what grade are you in?
help please need now
Answer:
it is second one
Explanation:
thanks
Which sample of matter can be separated into different substances by physical means
Answer:
a heterogeneous mixture
Explanation:
an example would be sand and water because it can be filtered which is a physical mean of separation.
Answer:
Heterogeneous mixtures
Explanation:
It is composed of two or more types of matter that can be present in varying amounts and can be separated by physical means. Heterogeneous mixtures vary in composition from point to point; homogeneous mixtures have the same composition from point to point.
which factor is unable to determine the climate of an area
Answer:
The climate of any particular place is influenced by a host of interacting factors. These include latitude, elevation, nearby water, ocean currents, topography, vegetation, and prevailing winds.
Explanation:
those are what does not affect climate
Which of the following describes a nonmetal
A:brittle shiny and solid at room temperature
B:brittle dull and low density
C:malleable shiny and able to conduct electricity
D:malleable dull and solid liquid or gas at room temperature
Answer:
b is the answer
Explanation:
non metals are not shiny, brittle, unmalleable, and are poor conductors of thermal energy and electrical current.
A nonmetal is brittle, dull, and low in density.
• Non-metals refer to the elements that produce negative ions by gaining or accepting electrons. The non-metals generally possess 4, 5, 6, or 7 electrons in their valence shell. The non-metals are those, which are devoid of all the metallic properties.
• The non-metals in their solids-state are brittle, thus, they lack ductility and malleability exhibited by the metals.
• The non-metals are not shiny like metals, they are dull in color.
• The non-metals seem to possess low density, primarily as non-metals seem to prevail either in a liquid or solid-state. The non-metals lack the dense and closed packing in the lattice, which is seen in metals.
Thus, non-metals are brittle, dull, and low in density.
To know more about:
https://brainly.com/question/17811524
Are two atoms of the same element identical?
Answer:
Depends on if the atoms have the same amount of atomic mass and if they have the same amount of ions, or none at all.
Explanation:
They can be the same atom, but if they don't have the same amount of protons, electrons, and neutrons, they aren't identical.
An ion from a given element has 24 protons and 22 electrons.
What is the charge on the ion? fill in the blank 1
What is the name of the element? fill in the blank 2
What is the symbol for the ion? '
Answer:
Explanation:
The charge on the ion is 24 protons - 22 electrons = 2+
The element is Chromium (number 24 on the periodic table).
Cr^2+
CALCULATE SCIENTIFIC NOTATION (Add and Subtract)
1) 9 × 103 + 2.3 × 104
2) 15 × 102 + 5.2 × 105
3) 10 × 104 + 2.8 × 106
4) 7.0 × 103 + 8.6 × 104
5) 3.0 × 104 + 14.5 × 105
6) 8 x 104 – 2.7 x 102
7) 5.0 x 103 – 8.9 x 104
8) 7.0 x 103 – 8.20 x 102
Answer:
1. 1166.2
2. 2076
3. 1336. 8
4. 733.04
5. 1834.5
6. 556.6
7. - 410.6
8. 836.4
Explanation:
1.9 x 103 =928
What is the definition of the word: Property (the scientific definition A makes up matter; makes up the world around us B an object or diagram C something that can be observed about a substance D to change the position of something HEalPPPPPPpPP
Answer:
i feel like the answer is A
How many C atoms are there in a sample of C,H, that contains 6.59 x 1026 H atoms?
A. 1.98 x 1027 C atoms
B. 2.47 x 1026 C atoms
C. 4.94 x 1026 C atoms
D. 3.17 x 1024 C atoms
Answer:
bill gates
Explanation:
Explain the difference between the organism, population, and community levels of ecological organization
Answer:
A population is a group of organisms belonging to the same species that live in the same area and interact with one another.
Explanation:
Levels of Ecological Organization
Level # 2. Population:
Level # 3. Community:
Level # 4. Ecosystem:
Level # 5. Biome:
Level # 6. Biosphere:
Aluminum metal reacts with chlorine gas to form aluminum chloride. The reaction can be represented by the following balanced chemical equation:
2 Al(s) + 3 Cl2(g) → 2 AlCl3(s).
If you were trying to react 52.9 grams of chlorine gas completely, how many grams of aluminum would you need?
_____________________ [grams of Aluminum] Do NOT enter the unit in your answer. Report your answer with 3 SFs.
Given to us is the Reaction of Aluminium metal with Chlorine gas . That is ,
[tex]\boxed{\red{\bf \underset{\blue{Aluminium}}{2Al(s)}+\underset{\blue{Chlorine}}{3Cl_2(g)}\longrightarrow \underset{\blue{Aluminium\: chloride}}{2AlCl_3}}}[/tex]
Now Mass of 1 mole aluminium = 27g . So mass of 2 moles of it would be 27×2 g = 54g .
Also , Mass of 1 mole of chlorine gas = 35.5 g . So mass of 2 Atoms will be 71g . And mass of 3 moles of atom will be 71 × 3g = 213g .
Now , use unitary method ;
213 g of Chlorine reacts with 54g of Aluminium.
1 g of Chlorine will react with [tex]\sf\dfrac{54g}{213g}[/tex] of Aluminium.
Hence 52.9 g of Chlorine will react with [tex]\sf \dfrac{54}{213}\times52.9g[/tex]=[tex]\bf 13.41g[/tex] of Aluminium.
What do you think makes an atom “neutral or ion”?
Plz help, i will give five stars and brainliest!
Answer: neutral
Explanation: An atom is made up of three major sub-atomic particles namely protons, electrons and neutrons. The electrons form a cloud around the nucleus and are bound to the nucleus by electromagnetic forces.
Which is the correct order of scientists?
Group of answer choices
Bohr, Dalton, Rutherford, Thomson
Rutherford, Thomson, Dalton, Bohr
Dalton, Thomson, Rutherford, Bohr
Thomson, Dalton, Rutherford, Bohr
What is the primary energy conversion that takes place in plants during photosynthesis? A. Electrical energy to heat energy B. Heat energy to chemical energy C. Light energy to chemical energy O D. Chemical energy to heat energy
Answer:
Photosynthesis in plants converts solar energy into chemical energy using electrons and protons from water. ... In the energy-transduction reactions, solar energy is converted into chemical energy in the form of two energy-transporting molecules, ATP and NADPH.
Answer:
light energy to chemical energy :]
Explanation:
Complete the Lewis Dot structure for the molecule H-C≡N and determine how many bonding and non-bonding electrons nitrogen has:
Answer:
I believe that in H-C≡N, Nitrogen has 4 bonding electrons and 2 non-bonding electrons.
(:
Explanation:
The image below shows uncharged particles bouncing around.
State of Matter
Which state of matter is most likely represented in the image? (5 points)
Gas
Solid
Liquid
Plasma
This problem is providing information about the states of matter and a given diagram showing a molecular arrangement it has. Thus, we can start off by analyzing the attached file, which shows molecular arrangements and movements each state exhibits.
Solids are quite organized so that they are able to form molecular networks in which molecules vibrate but do not displace anywhere. Liquid molecules are close enough to have small movements and vibrations but are not able to form any organized network.
Gases, however, exhibit no molecular organization but large movements inside the container whose walls the gas constantly crash against. Plasma do not have any order neither yet it contains ions.
In such a way, since the given diagram do not have any apparent order or ion, we infer this is about a gas that moves into the container and crash against its walls.
Learn more:
https://brainly.com/question/18538345https://brainly.com/question/9402776Unit for mass, volume and density
Answer:
kg, m^3, kg/m^3
Explanation:
the SI units for these are:
mass: kilogram
volume: cubic meter
density: kilogram per cubic meter
who can do my chemistry homework for 20$?? First come
Answer:
WTH? That is WOW....-_-
Answer:
wow
Explanation:
wow
What type of energy transfer is taking place when someone plays a violin?
A. Potential energy to kinetic energy
B. Elastic energy to electromagnetic energy
C. Kinetic energy to sound energy
D. Sound energy to heat energy
Answer:
C.
Explanation:
The movement of the bow is Kinetic Energy.
Answer: C. Kinetic energy to sound energy
Explanation: The vibration of the string is kinetic energy that transforms into sound energy.
Use the drop-down menus to complete each sentence.
A
is an organism that eats other organisms to gain energy; it is also called
.
A
is an organism that makes its own food; it is also called
.
A
is an organism that breaks down waste and dead organisms.
Answer:
A consumer is an organism that eats other organisms to gain energy; it is also called a heterotroph.
A producer is an organism that makes its own food; it is also called an autotroph.
A decomposer is an organism that breaks down waste and dead organisms.
Explanation:
Green plants are examples of autotrophs that make their own food by photosynthesis - they don't rely on other organisms to provide them with energy.
In contrast, many organisms rely on other organisms as an energy source. These organisms are called consumers or heterotrophs. They consume producers and other consumers.
Decomposers such as some fungi, bacteria, and certain insects break down dead or decaying biological material and recycle the nutrients back into the soil.
Answer:consumer a heterotroph producer an autotroph decomposer
Explanation:
What type of energy is elastic energy?
A. Kinetic energy
B. Chemical energy
C. Nuclear energy
D. Potential energy
ASAP
Answer:
D. potential energy
Explanation:
I want someone he is good in chemistry
Answer:
.I can help you.....Explanation:
am good atmoles
bonding
balancing equations
and set ups
How many moles are in 1.93x1023 particles of Na3PO4?
Answer:
The answer is 0.32 molesExplanation:
To find the number of moles given the 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
N = 1.93 × 10²³ particles
We have
[tex]n = \frac{1.93 \times {10}^{23} }{6.02 \times {10}^{23 } } \\ = 0.320598006...[/tex]
We have the final answer as
0.32 molesHope this helps you
No. of particles of Na₃PO₄ = 1.93×10²³
We have to find number of moles of the given compound[tex].[/tex]
Number of moles cam be found by using this formula :
[tex]\bigstar\:\boxed{\bf{\purple{n=\dfrac{N}{N_A}}}}[/tex]
n denotes number of molesN denotes number of particles[tex]\sf{N_A}[/tex]denotes avogadro's constantWe know that,
[tex]\bf{N_A}[/tex] = 6.022×10²³★ Calculation :
➠ n = N/[tex]\sf{N_A}[/tex]
➠ n = (1.93×10²³)/(6.022×10²³)
➠ n = 0.32 moles
★ Explore More :
n = weight / Molar massn = volume / 22.4Hope It Helps!How is color a physical change
Answer:Physical changes involve states of matter and energy. No new substance is created during a physical change, although the matter takes a different form. The size, shape, and color of matter may change. Physical changes occur when substances are mixed but don't chemically react.
Explanation:
How can changing the shape of an object lower its overall density?