Answer:
1. true
2. false
Explanation:
PROMISE PROMISE to make the most of the su in the WORLD CUP and chemica are u doing the meetings with
If a laser operating at a wavelength of 488 nm and a power of 123.0 mW is turned on for 18.73 minutes, how many photons has it emitted?
Answer:
3.39e+20
Explanation:
what is the wavelength of microwaves if the frequency is 2.45x 10^9 HZ?
Wavelength = Speed of Light ÷ Frequency
= (2.99 × 10⁸ m/s) ÷ ( 2.45 × 10⁹ /s)
= 1.22 × 10⁻¹ m
The wavelength of a light of frequency 2.45 × 10⁹ /s is 1.22 × 10⁻¹ m.
Notes:
Hz ≡ /s
suppose that hypothetical element Jovian occurs as three isotopes with mass numbers 44, 46, and 48 respectively. If, in nature, Jovian occurs as Jovian-44 approximately 22.4% of the time, and as Jovian-46 approximately 44.0% of the time, what is the best value to use as the atomic mass of Jovian?
Answer:
46.2 amu
Explanation:
The average atomic mass of an element can be determined using the percentage abundance and mass of its isotopes. The average atomic mass of the hypothetical element Jovian is 46.2 amu.
What is average atomic mass?Most of the elements have two or more isotopes in nature with different percentage abundance and mass. The average atomic mass of the element is then calculated using the formula written below:
Average atomic mass = % abundance /100 × mass of isotope 1 + % abundance /100 × mass of isotope 2 + .....
Given the mass % abundance of Jovian -44 = 22.4 %
Jovian- 46 = 44 %
Jovian -48 = (100 - (44 + 22.4)) = 33.6 %
Average atomic mass of Jovian = ( 22.4 /100 × 44 ) + ( 44 /100 × 46) + ( 33.6 /100 × 48 ) = 46.2 amu
Therefore, the average atomic mass of the hypothetical element is 46.2 amu.
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How do anion formation and valence electrons relate?
Answer:
Atoms gain valence electrons to form anions.
Explanation:
When acids dissolve in water, what is released into the resulting solution?
H+ and OH-ions equally
H+ (hydrogen) ions
OH- (hydroxide) ions
Answer:
H+ (hydrogen) ions
Explanation:
Answer:
H+ (hydrogen) ions
Explanation:
how did dalton advance the atomic philosophy proposed by democritus
Answer:
(Hope this helps can I pls have brainlist (crown)☺️)
Explanation:
Dalton turned Democritus' views on atoms into a scientific theory by employing experimental methods. Atoms can join or detach during chemical processes, but they never transform into a different atom.
Dalton was an excellent polymath, a natural philosopher, and a real scientist. His thorough investigations prompted him to suggest an early atomic theory for which exceptions would be difficult to uncover today:
Dalton offered the following:
Atoms are microscopic particles that make up elements. Atoms of the same element have the same size and mass; however, atoms of other elements have varying sizes and masses when compared to atoms of other elements. Subdivision, creation, and destruction of atoms are all impossible.
All of these ideas were developed after a great deal of testing. Other researchers may replicate his work, and new findings could be included into this atomic idea.
Democritus, on the other hand, was a 5th-century BC Greek philosopher. He conducted no experimental work as far as we know, and none of his publications have survived. He postulated that matter was made up of a single indivisible element known as an atom; the word atom originates from the Greek word oos, which meaning "uncuttable" or "indivisible." So the name atom might be a homage to Democritus.
Mitotic cyclins control the progression of S phase and mitosis. G1 phase and G2 phase. S phase and G2 phase. G2 phase and mitosis
Answer:
D
Explanation:
Its D
Answer:
Its d for edge
Explanation:
Answer the following:
What are 3 types of physical properties for nitrogen?
What are 2 types of chemical properties for nitrogen?
Answer:
What are 3 physical properties of nitrogen?
Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.09 percent of Earth's atmosphere by volume.
What are 2 chemical properties of nitrogen?
Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.09 percent of Earth's atmosphere by volume. Nitrogen gas is an industrial gas produced by the fractional distillation of liquid air or by mechanical means using gaseous air.
Which of the following are properties of compounds formed by covalent bonding (Select all that apply)
1. When you dissolve an covalent compound in water, the solution does not conduct electricity.
2. Covalent compounds often have lower melting points than ionic compounds.
3. When you dissolve an covalent compound in water, the solution conducts electricity.
4. Covalent compounds form when combining two or more nonmetal atoms.
5. Covalent compounds form when combining a two metal atoms.
6. Covalent compounds form when combining a metal atom with a nonmetal atom.
Answer:1, 2, and 4
Explanation:
covalent bonds are not ionic. the elements SHARE electrons
Which of the following are properties of compounds formed by covalent bonding (Select all that apply)
1. When you dissolve an covalent compound in water, the solution does not conduct electricity.
2. Covalent compounds often have lower melting points than ionic compounds.
3. When you dissolve an covalent compound in water, the solution conducts electricity.
4. Covalent compounds form when combining two or more nonmetal atoms.
5. Covalent compounds form when combining a two metal atoms.
6. Covalent compounds form when combining a metal atom with a nonmetal atom.
The properties of covalent compounds are option 2, 3 and 4. Covalent bonds are weaker than ionic bonds.
What are covalent bonds?Covalent bonds are formed by sharing electrons between two atoms. Non metals with comparable electronegativities forms covalent bonds. They are weaker than ionic bond. Thus have lower melting point.
Melting point depends on the bond strength that's why covalent compounds have lower melting point compared with ionic bonds.
Polar covalent bonds can conduct electricity when dissolved in water because of the presence of free electrons. Thus option 3 is correct.
Hence, the properties in option 2, 3 and 4 are correct for covalent compounds.
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Someone help me with this I will make you brain
Define what the goldilocks zone in our solar system ?
Answer:
the "goldilocks zone" is the habitable zone around a star where it's not too hot and not too cold, so liquid water and life can exist on the planets in this zone.
Explanation:
The distance Earth orbits the Sun is just right for water to remain a liquid and for life to not be frozen or fried. This distance from the Sun is called the habitable zone, or the Goldilocks zone.
29. Which type of orbital is shown?
Z
Y
Х
Answer:
b
Explanation:
Do you think the Clean Air Act was a good solution to the changing environment in England? Explain.
Americans breathe less pollution and face lower risks of premature death and other serious health effects. Environmental damage from air pollution is reduced. The value of Clean Air Act health benefits far exceeds the costs of reducing pollution. ... New plants and factories install modern pollution control technology.
Is this statement true or false?
A chemical reaction is balanced when the number of atoms of each element is the same for both the reactants and the products.
true
false
Answer:
truetysm
tysm
tysm dear
plz help fast. Which of the following represents a chemical change? (2 points)
1. decomposition of stone due to acid rain
2. iron's attraction to a magnet
3. the pink color of a rose
4. rocks being smoothed by rapid water movement
Answer:
1. Decomposition of stone due to acid rain.
3. The pink color of a rose.
Explanation:
Chemical changes always end up with new products in an equation, or it has always something to do with chemicals. Physical changes on the other hand, do not result in new products and it just changes the physical properties and physical state of matter of the object.
What forms a weak acid?
(Hint: Carbonation)
A) carbon dioxide/iron
B) carbon dioxide/water
C) carbon dioxide/materials
D) Oxygen/rust
Someone pls help me I will make you you brain
Answer:It’s cyclone movement
Explanation:
Help meeeeeeeeeeeeeee
Answer:
Copper = Cu
Gold = Ag
Iron = Fe
Potassium = K
Which of the following is a physical change?
evaporation
explosion
rotting of food
corrosion
Answer:
i believe it is c
evaporation
Explanation:
Hope it's the correct one if not very sorry.
a measure of the ability of an atom in a chemical compound to attract electrons is called
during which two processes does a substance release energy?
Answer:
Freezing and condensation
Explanation:
Because they are exothermic, they release energy
pls help ASSSAPPPP!!!!
Answer:
b or d
Explanation:
Answer:
The answer is B (it's reactivity)
draw the skeletal structure of the alkyl halide that forms the following alkene as the only product in an elimination reaction. you do not need to show lone pairs.
The alkyl halide that forms the alkene shown as the only product in an elimination reaction is bromomethyl cyclohexane.
An elimination reaction is a reaction in which two atoms are removed to create a double bond. Elimination reaction is a type of reaction that is common to alkyl halides.
In this reaction, a hydrogen atom and a halogen atom are both removed to yield a double bond. The structure of the product depends on the structure of the reactant alkyl halide.
Bromomethylcyclohexane shown in the image attached yields the alkene product in the image attached as the only product when it undergoes elimination reaction.
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if you answer this question right you get 100 points. What is my favorite color it is a 4 letter word and it ends with e
° °
∵ω∵
Answer:
Blue!!
I think it is blue!
is it blue cuz i think its blue
What kind of interaction
(attraction/repulsion) will happen
between the core electrons and the
valence electrons?
Cho 200 g dung dịch NaCl 0,5M tác dụng hết với 400 ml AgNO3. Sau phản ứng thu được kết tủa và dung dịch không màu
a, Viết phương trình hóa học xảy ra?
b, Tính khối lương kết tủa tạo thành
c, Tính nồng độ mol của dung dịch AgNO3 đã tham gia phản ứng.
Answer:
Explanation:
a. NaCl+ AgNO3-----> NaNO3+ AgCl
b. Số mol của NaCl= 0,2*0,5= 0,1 (mol)
------> Số mol của kết tủa AgCl tạo thành= 0,1 mol (dựa vào phương trình hóa học)
-----> Khối lượng của kết tủa AgCl tạo thành= 0,1*143,5=14,35(g)
c. Số mol của AgNO3= số mol của NaCl= 0,1 (mol)
------> Nồng độ mol của dd AgNO3 đã tham gia phản ứng= [tex]\frac{0,1}{0,4}[/tex]=0,25(M)
write down ten laboratory safety rules
laboratory safety rules:
~Avoid wye contact with all chemics
~ Avoid skin contact with all chemicals
~Always wear safety glasses
~Don't eat in the lab
~Don't drink anything in the lab
~Avoid wearing jewellery
~Don't taste or sniff any chemicals
~Kn0w emergency exit routes
~Never leave containers of chemicals open
~Avoid distracting anyone else working in the lab
Hope this helped you- have a good day bro cya)
Does sodium (Na) and argon (Ar) on the periodic table have similar properties? Explain in terms of location on the periodic table
Sodium (Na) and Argon (Ar) on the periodic table does not have similar properties.
PERIODIC TABLE:
Periodic table is the organized table that showcases the position of elements. The periodic table is organized into groups and periods. Groups of the periodic table is in a vertical format labeled 1 - 7 while the period is in a horizontal format labeled 1 - 7. Elements in the same group have the same number of valence electrons and hence, possess similar chemical properties. Sodium (Na) belongs to group 1 while argon is a noble gas, hence, they are not in the same group of the periodic table and cannot have same properties.Learn more at: https://brainly.com/question/24089206?referrer=searchResults
how is an inoculating loop or needle sterilized prior to use?
Answer:
it is placed over a bunsen burner to heat up and remove all bacteria
Explanation:
Please answer quickly
Answer:
a) II and III
is the correct