Answer:
replacement
Explanation:
What is the name for the group of unreactive elements on the periodic table?
Noble Gases, at least that's what I was told. Hope that helps.
A scientist claimed that he radiocarbon dated a fossilized skull of a dinosaur and found it to be about 63 million years old. Do you support his claim? Provide at least one scientifically based reason why you do or do not support the claim.
Answer:Since dinosaurs are thought to be over 65 million years old, the news is stunning - and more than some could tolerate. After the AOGS-AGU conference in Singapore, the abstract was removed from the conference website by two chairmen because they could not accept the findings. Unwilling to challenge the data openly, they erased the report from public view without a word to the authors. When the authors inquired, they received this letter:
Explanation:
i do not own my copyrights
how many elements are found in the third period. A.2 B.18 C.8 D.32
Answer:
8
Explanation:
u can find it on ur chemistry book
Answer:
C. 8
Explanation:
Check chemistry textbook
If 2.68 g of benzaldehyde are involved with the mixed aldol condensation reaction, how many moles of benzaldehyde are present? Round your answer to the correct number of significant figures. (reaction has 2:1 mole ratio) 1 acetone is reacted with 2 benzaldehyde
Answer:
The number of moles of benzaldehyde = 0.0253 moles
Explanation:
The molecular formula of benzaldehyde is C₇H₆O
Its molecular mass is calculated from the atomic masses of the constituent atoms.
C = 12.0 g: H = 1.0 g; O = 16.0 g
Molecular mass = ( 12 * 7) + (1 * 6) + (16 * 1) = 106.0 g/mol
Number of moles of substance = mass of substance/ molar mass of the substance
mass of benzaldehyde = 2.68; molar mass = 106.0 g/mol
Number of moles of benzaldehyde = 2.68 g/ 106 g/mol = 0.0253 moles
Therefore, the number of moles of benzaldehyde = 0.0253 moles
Iron(III) nitrate + potassium sulfide product names
What can you conclude from the figure shown?
(a) The Hund's rule has been violated
(b) The Aufbau principle has been violated
(c) The Pauli's Exclusion principle has been violated
(D) This is a valid orbital diagram
Answer:
A. Hund's rule has been violated
Explanation:
There must be one electron with the same spin in each orbital of the same energy before you can put two in the same orbital. In the photo, the 2s sublevel is completely filled before the 1s sublevel (if anything the 1s should have an up spin and down spin, with the 2s having one up spin).
From the figure , it can be concluded that Hund's rule is violated as 1s sub shell is not completely filled before moving to the 2s sub shell.
What is Hund's rule ?Hund's rule of maximum multiplicity is an atomic rule which is based on the observation of atomic spectra and is used for prediction of ground state of an atom or molecule which have one or more open electronic shells.
It states that, for a given electronic configuration lowest energy term is the one which has greatest value of multiplicities of spin. It implies to the fact that if two orbitals are present which are of equal energy, electrons will occupy them singly before pairing of electrons take place.
The rule finds tremendous use in atomic chemistry,spectroscopy and quantum chemistry.
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What pH scale number represents a neutral.
What pH scale number represents a neutral.
The answer is 7
What are four the main causes of erosion? wind, water, ice, gravity O biological, chemical, mechanical, subterranean O freezing, hydration, oxidation, salt crystallization O seismic movement, vocalism, mountain building, ocean waves
Answer:
Water, wind, ice, and gravity
Explanation:
I took the quiz ;)
What is the trend in atomic radius as you go across a period
Answer: Atomic radius decreases across a period and increases down a group.
Four students rolled a ball down a slide on the play ground which ball has the greatest applied force
Core electrons shield what from the pull of the nucleus?
A. Identical electrons
B. Neutrons
C. Valence electrons
D. Protons
Answer:
C. Valence electrons
Explanation:
Please mark my answer as brainliest, I would appreciate it.
:)
What is the atomic radius
Answer:
The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons.
A 10 gram sample of iron reacts with oxygen to form 18.2 grams of ferric oxide. How many grams of oxygen reacted?
Answer:
[tex]\boxed {\boxed {\sf 8.2 \ grams}}[/tex]
Explanation:
According to the Law of Conservation of Mass, the mass of the products must equal the mass of the reactants.
mass products = mass reactantsIn this problem, the reaction is:
[tex]iron + oxygen = ferric \ oxygen[/tex]
The reactants are iron and oxygen. We know the mass of the iron sample is 10 grams. The product is ferric oxide. The mass of the ferric oxide sample is 18.2 grams.[tex]10 \ g + oxygen=18.2 \ g[/tex]
We want to find how many grams of oxygen reacted. We have to get the oxygen by itself. 10 is being added to oxygen. The inverse of addition is subtraction. Subtract 10 from both sides of the equation.
[tex]10 \ g - 10 \ g+ oxygen = 18.2 \ g - 10 \ g[/tex]
[tex]oxygen= 18.2 \ g - 10 \ g[/tex]
[tex]oxygen= 8.2 \ g \\[/tex]
8.2 grams of oxygen reacted with 10 grams of iron to form 18.2 grams of ferric oxide.
Consider phosphoric acid, H3PO4. What is the total number of moles of H+ available for reaction in 4.50 L of 0.750 MH3PO4? Write your answer as a numerical value without any units. Type your numeric answer and submit
If 7.75 L of radon gas is at 1.55 atm and -19 °C, what is the volume at STP?
The volume at STP is 12.9L.
What symptoms are caused by radon gas?
Possible symptoms include shortness of breath (difficulty breathing), a new or worsening cough, pain or tightness in the chest, hoarseness, or trouble swallowing. If you smoke and you know you've been exposed to high levels of radon, it's very important to quit smoking.
What is the primary reason for radon gasoline in the home?It comes from the natural decay of uranium which is determined in nearly all soils. It typically moves up via the floor to the air above and into your private home through cracks and other holes in the basis. your home traps radon inner, which it is able to build up.
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Give the names of the elements combined in barium sulfide.
Answer:
Barium and sulpher are the elements that forms barium sulphide .
And its molecular fomula is BaS.
Explanation:
There are two types of chemical compound one is covalent compound and other is ionic compound, covalent compound formed by sharing of electron and ionic compound formed by complete transfer of electron. Therefore, in barium sulfide, barium and sulfur elements are present.
What is chemical Compound?Chemical Compound is a combination of molecule, Molecule forms by combination of element and element forms by combination of atoms in fixed proportion.
An ionic compound is a metal and nonmetal combined compound. Ionic compound are very hard. They have high melting and boiling point because of strong ion bond. In barium sulfide, barium and sulfur elements are present. The molecular formula of the compound is BaS.
Therefore, in barium sulfide, barium and sulfur elements are present.
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What does scientist use to deign their experiments
Answer:
a chart
Explanation:
a chart a chart is the answer
What is the degree of oxidation of a simple substance
Answer: The oxidation state of a free element (uncombined element) is zero. For a simple (monoatomic) ion, the oxidation state is equal to the net charge on the ion. For example, Cl– has an oxidation state of -1. When present in most compounds, hydrogen has an oxidation state of +1 and oxygen an oxidation state of −2.
hope this helps........ Stay safe and have a Merry Christmas!!!!!!!!! :D Explanation:
Do you think it is important for archaeological sites to be protected from development once they are discovered? What are the pros and cons of each side of this issue? Once discovered, should artifacts be left as they are, or removed and displayed for others to learn about? What are the pros and cons of each option? How can cultural or societal influences affect the progression of scientific discovery? Do those influences normally have a positive or negative effect on science's ability to advance?
Answer: lessons and benefits can seem removed from everyday life. ... If they determine a site is significant, it is ... CRM exists because legislators and their con- ... romance of excavation and discovery of the past for ... Archaeology permits intensive study of a single culture over time, removing the myth
When circumstances are right, most materials undergo a process called thermal expansion. Which statement best describes the cause and effect of thermal expansion? Group of answer choices Matter is heated, and its particles spread out more. Matter is heated, and its particles move closer together. Matter is cooled, and its particles move closer together. Matter is cooled, and its particles spread out more.
Answer: Matter is heated, and its particles spread out more
Explanation:
Thermal expansion occurs when there's an expansion of an object or material or when an object becomes bigger because of a rise in its temperature. This brings about the faster movement of the heated molecules and the atoms spreading out.
Therefore, the cause and effect of thermal expansion will be that when matter is heated, and its particles spread out more.
Can you please answer this for me please?
Which form of energy is stored chemical energy and example of?
A. Kinetic energy
B. Potential energy
C. Gravitational energy
D. Powered energy
WARNING: Sorry I'm only in 5th grade so if you see my level as collage I had to put that because it would not let me put anything else
Answer:
Well its B im sorry if im wrong.
Explanation:
How many minutes will it take to plate out 4.50 g of Cu from a solution of Cu(NO3)2 (aq) onto the cathode of an electrolytic cell when 8.00 A of current are used?
a. 28.5 min.b. 3.06 × 10^−9 min.c. 14.2 min.d. 1.82 × 10^3 min.
Answer:
a. 28.5 min
Explanation:
The computation of the number of minutes would it take to plate out is as follows:
Cu+2 +2e [tex]\rightarrow[/tex]Cu
The two moles of electrons could be generated for the copper i.e. deposited
Now
moles of copper is
= 4.5 ÷ 63.5
= 0.071
The 63.5 represents the atomic copper weight
Now mole of electrons deposited is
= 0.071 × 2
= 0.142
Now
quantitiy of electricity needed
= moles of electrons deposited × 96500
= 0.142 × 96500
= 13703 coulums
As per electricity quantity needed
= current × time(seconds)
= 13703 = 8 × t
t = 13703 ÷ 8
= 1713 seconds
= 1713 ÷ 60 minutes
=28.5 min
hence, the correct option is a.
Which two molecules are broken down in your cells during cellular respiration? Whoever is correct gets thanks and brainliest
Answer:
glucose and oxygen
Explanation:
Cellular respiration is the aerobic process by which living cells break down glucose molecules, release energy, and form molecules of ATP. Overall, this three-stage process involves glucose and oxygen reacting to form carbon dioxide and water.
Difference between Electron Proton and Neutron?
Answer:
protons-positively charged
neutrons-uncharged
electrons- negatively charged
The differences are protons give out a positive charge neutrons are neutral and electrons give out negative charge.
Another one is the fact they are located on specific separate parts of an atom and each atoms consists a different amount each charge hope this helped :)
4. How many moles of water are produced when 3.25 moles of CO2 are formed?
Answer:
6.50 mol
Explanation:
The question is incomplete but I looked it up on the web.
How many moles of water are produced when 3.25 moles of CO₂ are formed during the combustion of methyl alcohol (CH₃OH)?
Step 1: Write the balanced equation
2 CH₃OH + 3 O₂ → 2 CO₂ + 4 H₂O
Step 2: Establish the appropriate molar ratio
According to the balanced equation, the molar ratio of CO₂ to H₂O is 2:4.
Step 3: Calculate the moles of water formed with 3.25 moles of carbon dioxide
We will use the established molar ratio.
3.25 mol CO₂ × (4 mol H₂O/ 2 mol CO₂) = 6.50 mol H₂O
How many moles of O2 are needed to burn 2.56 moles of CH3OH?
Answer:
[tex]n_{O_2}=3.84molO_2[/tex]
Explanation:
Hello!
In this case, since the combustion reaction of methanol is:
[tex]CH_3OH+\frac{3}{2} O_2\rightarrow CO_2+2H_2O[/tex]
In such a way, since there is 1:3/2 mole ratio between methanol and oxygen, we can compute the moles of oxygen that are needed to burn 2.56 moles of methanol as shown below:
[tex]n_{O_2}=2.56molCH_3OH*\frac{\frac{3}{2}molO_2}{1molCH_3OH} \\\\n_{O_2}=3.84molO_2[/tex]
Best regards!
You have 3.00 L of a 3.74 M solution of NaCl(aq) called solution A. You also have 2.00 L of a 2.00 M solution of AgNO3(aq) called solution B. You mix these solutions together to make solution C. Calculate the concentration (in M) of Cl ions in solution C.
Answer:
[tex]M=2.24M[/tex]
Explanation:
Hello!
In this case, since the molarity and volume of the solutions are given, we are able to compute the moles of chloride ions as they are present in NaCl only:
[tex]n_{Cl^-}=3.00L*3.74\frac{molNaCl}{L}*\frac{1molCl^-}{1molNaCl} =11.22molCl^-[/tex]
Next, since the mixing of solution A and B lead to a volume of 5.00 L, the concentration of chloride ions turns out:
[tex]M=\frac{11.22mol}{5.00L}=2.24M[/tex]
Best regards!
1. What is a wave?
a.) a vibrating disturbance that transfers energy from place to place
b.) a material which a wave travels through
c.) an area where coils spread out
d.) the maximum distance a medium moves from its rest position
Answer:
A.
Explanation:
A wave is a disturbance that moves energy from one place to another. Only energy — not matter — is transferred as a wave moves. The substance that a wave moves through is called the medium. That medium moves back and forth repeatedly, returning to its original position. But the wave travels along the medium
Which of the following best describes the difference between a mixture and a pure substance? A. A mixture has the same properties throughout; a pure substance has the different properties throughout. B. A mixture has different properties throughout; a pure substance has the same properties throughout A mixture is made up of only one type of atom; a pure substance is made up of more than C. one type of atom. A mixture is made up of more than one type of atom; a pure substance is made up of only D. one type of atom.
Answer:
B. A mixture has different properties throughout; a pure substance has the same properties throughout
Explanation:
We have two classes of substances which are pure and impure substances.
Pure substances are elements and compounds
Impure substance are simply mixtures.
Mixtures have the following properties;
Their composition is indefinite i.e. they consist of two or more elements and or compounds in any proportion by mass. Constituents retain their identities i.e. physical properties are retained. Constituents react differently to changed conditionsThey can easily be separated by physical methods.Which is the order of these solutions from strong acid to strong base?
Solutions:
household ammonia
battery acid
baking soda
stomach acid
antacid
A-stomach acid household ammonia battery acid antacid baking soda
B-battery acid stomach acid antacid baking soda household ammonia
C-battery acid stomach acid baking soda antacid household ammonia
D-stomach acid battery acid antacid baking soda household ammonia
Answer:
First is battery acid with a pH of 1, second is stomach acid with a pH of 1.5-3.5 (depends), third is antacid with a pH of 7, fourth is baking soda with a pH of 9, and finally, fifth is household ammonia with a pH of 11.
Here is a picture of the pH levels to better help you understand.
Answer:
b
Explanation: