Answer: There are [tex]47.6\times 10^{23}[/tex] molecules in 7.9 mol of [tex]H_2O_2[/tex]
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
1 mole of [tex]H_2O_2[/tex] molecule contains = [tex]6.023\times 10^{23}[/tex] molecules
Thus 7.9 mole of [tex]H_2O_2[/tex] molecule contains = [tex]\frac{6.023\times 10^{23}}{1}\times 7.9=47.6\times 10^{23}[/tex] molecules
Thus there are [tex]47.6\times 10^{23}[/tex] molecules in 7.9 mol of [tex]H_2O_2[/tex]
The number of......... in an atom is the difference between the mass number and the atomic number
A-Electrons
B-Neutrons
C-Protons
Answer: While the mass number is the sum of the protons and neutrons in an atom, the atomic number is only the number of protons. The atomic number is the value found associated with an element on the periodic table because it is the key to the element's identity.
MARK ME BRAINLIST
the number of molecules present in 0.036g of water
Answer:
5
Explanation:
. ILL GIVE BRAINLY
Why does the top layer of the rainforest receive the most sunlight?
Its tall trees rise above all the other layers.
The plants there have very broad, dark green leaves.
It has many trees and vines.
The trees there are thicker than in the other layers.
Answer:
It has many trees and vines
Explanation:
Answer:it’s tall trees rise above all the other layers
Explanation:
The quiz said so
please help!!! will give brainliest!!! 30 points! (need to put roman numeral in answer)
1. Nickel (II) Bromide
2. Iron (II) Oxide
3. Iron (III) Oxide
4. Tin (IV) Chloride
5. Lead (IV) tetrachloride
6. Tin (II) Bromide
7. Chromium (III) Phosphide
8. Iron (II) Fluoride
9. Gold (III) Chloride
I hope this helps. I'm more than 100% sure that all the answers except for number 7 are correct. I knew all of them off the top of my head except for this one. I hope the other answer has the correct answer for that one. Good luck and have a great day.
AHHH I need help ASAP what does TAILS stand for in science??
[please answer fast!] If the hydroxide ion concentration is 2x10^-3 M, what is the pH of the solution? Show your working.
Answer:
pH = 11.30
Explanation:
pH is defined as -log [H⁺]
To find [H⁺] from [OH⁻] -Concentration of hydroxide ion-, we must use the equilibrium of water:
H₂O(l) ⇄ H⁺(aq) + OH⁻(aq)
Keq = 1x10⁻¹⁴ = [H⁺] [OH⁻]
[H⁺] = 1x10⁻¹⁴ / [OH⁻]
[H⁺] = 1x10⁻¹⁴ / 2x10⁻³M
[H⁺] = 5x10⁻¹²M
pH = -log (5x10⁻¹²M)
pH = 11.30Elements and compounds are usually more dense in their solid than in their
liquid state. However, water is one of the notable exceptions. The density
of ice is 0.917 g/mL, while the density of liquid water is 1.00 g/mL. What
natural phenomena does this explain?
Explanation:
The molecules in water is more tightly packed than in ice, so water has greater density than ice.
Na on the periodic table is the symbol for what?
Answer:
sodium
Explanation:
Na is the symbol for sodium on the periodic table
Answer: Sodium is a chemical element with the symbol Na (from Latin "natrium") and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is 23 Na.
Explanation:
c) A football feels hard on a hot day but feels softer in the evening
Answer: ^_^
Explanation:
its because during day time the ball becomes heated up and the air inside it try to come out as the heat air always try to go up swelling up the ball,
so in the evening when the air cools down the ball too cools down and air inside it also cools down making the ball feel soft,
Therefore, a football feels hard on a hot day but feels softer in the evening
Hope it helped u,
pls mark as the brainliest
^_^
Answer:
its because during day time the ball becomes heated up and the air inside it try to come out as the heat air always try to go up swelling up the ball,
so in the evening when the air cools down the ball too cools down and air inside it also cools down making the ball feel soft,
Therefore, a football feels hard on a hot day but feels softer in the evening
Hope it helped u,
pls mark as the brainliest
Explanation:
18.The Halogen family of elements all have 7 valence electrons. Which column would they be in?
a.01 (IA)
b.02 (IIA)
c.4 (IVA) or 14
d.7 (VIIA) or 17
HI PLEASE HELPPPL I NEED THIS DUE VERY SOON
9)
What is the precipitate resulting from the double-replacement reaction BaCl2(aq) + 2NaOH(aq)?
A. Ba(OH)2
B. NaCl
C. BaNa2
D. CI(OH)
Answer:
A
Explanation:
I just did this question in class:))
1. X-linked (also called sex-linked traits) are inherited on the _____ chromosome.
Answer:
Genes on the X chromosome are said to be X-linked. X-linked genes have distinctive inheritance patterns because they are present in different numbers in females (XX) and males (XY). X-linked human genetic disorders are much more common in males than in females due to the X-linked inheritance pattern.
Explanation:
What does it mean if a solution is a "weak acid "? Strong acid? Give logical ph values for each
Answer:
A weak acid is an acid that partially dissociates into its ions in an aqueous solution or water. In contrast, a strong acid fully dissociates into its ions in water. At the same concentration, weak acids have a higher pH value than strong acids.
Explanation:
:)
20 POINTS!!
__________ aid the immune system in mounting attacks against cancer cells by targeting antigens only found on the surface of cancer cells.
A. Monoclonal antibodies
B. Interferons
C. CRISPR
D. Vaccines
E. Interleukins
Answer:
B. Interferon
Explanation:
interferon targets any lingering melanoma cells and prevents them from spreading and growing.
HELP PLS PLS PLSSSS
Energy is converted from kinetic energy to potential energy when you
ski down a hill.
climb a mountain.
run around a track.
sit at a desk in physics class
Answer:
CLIMB A MOUTAIN
Explanation:
B
Does hydrogen have similar physical properties to alkali metals?
Answer:
YESExplanation:
because it contain 1 electron in its outermost shellreaction type
__HCl + __Mg -> __MgCl2 + __H2
What are Rhodium isotopes used for?
Answer:
Rhodium is used to make electrical contacts, as jewelry and in catalytic converters, but is most frequently used as an alloying agent in other materials, such as platinum and palladium. These alloys are used to make such things as furnace coils, electrodes for aircraft spark plugs and laboratory crucibles.
Explanation:
Why is salad dressing a solution?
Explanation:
A prime illustration of sour salad dressing formulas and suspension. Vinegar is also an acetic acid product which is dispersed in water, so we can't even see molecules in the oil. The removal throughout the liquid phase to make a solution.
Which phrase describes runoff?
1.underground water that flows into lakes
2.river water that empties into an ocean
3.water from streams that flows into larger rivers
4.water from rain and snow that travels to streams
Please help!
Explanation:
water from rain and snow that travels to streams
Please help!
Water from a rain and snow that travels to streams are examples of run off. These natural processes are part of water cycle and balance the water content in the atmosphere and hydrosphere.
What is water cycle ?Water cycle is a geological phenomenon to balance the water content in the atmosphere, hydrosphere and in the biosphere. The water bodies evaporate by the heat radiated by sun.
The air moisture can be restored to the land through the cooling of the vapor and pour as rain. This best illustrates the interaction between atmosphere and hydrosphere.
Rain, snow, sleet, or hail that reaches a surface stream without ever going below the soil's surface is referred to as surface runoff. It differs from direct runoff, which is runoff that directly reaches surface streams following rainfall or snowmelt. Hence option 4 is correct.
Find more on water cycle :
brainly.com/question/1151425
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which is the odd man out? diamond,coal, graphite, bronze.answer with an explanation
define p-block element?
Answer:
[tex]\boxed {\boxed {\sf D. \ Bronze}}[/tex]
Explanation:
Let's analyze the answer choices.
The first answer choices. diamond, coal, and graphite, all have something in common. They are allotropes of carbon. They are made of the same element, but each has a different arrangement of atoms, which leads to different properties.
Bronze is an alloy of copper, tin, and other metals. It's not an allotrope of carbon or related to the other answer choices. Therefore, it is the odd one out.
i need help with chemistry asap. the copounds Ch3Oh and Ch3CooH react in the presence of an acid catalyst to form. A. a carboxylic B. an aldehyde C. a ketone and D. an ester.
Sharon puts a large pot of water on the stove to boil pasta. Then she starts to make a tomato sauce. When the sauce is cooking, she looks at the pot of water and thinks the water level is much lower than it was. How does this diagram of part of the water cycle help Sharon explain what happened to the pasta water?
Answer:
1. A
2. C
Explanation:
For the first question, we know that the water transformed into a gas. This fact eliminates choices C and D, primarily because they describe the change as "gas to liquid" instead of liquid to gas.
What separates B from A is that B is saying the liquid changed to a gas in response to sunlight, which is completely false and impertinent to the prompt.
A is the correct answer.
for the second question, we know that condensation causes clouds -- and that neither evaporation nor water vapor would clear clouds to make more of them, which eliminates choices B and D. Going back to condensation, the accumulation of water vapor plays a big role in the formation of clouds. While evaporation does play a part in [it] as well, condensation is what caused the sudden appearance of clouds in the troposphere.
C is the correct answer.
. How many grams of magnesium chloride can be produced by reacting 2 moles of chlorine gas with excess magnesium bromide? ____Cl2 + ____MgBr2 ___MgCl2 + ___Br2
Answer: 190 g of magnesium chloride can be produced by reacting 2 moles of chlorine gas with excess magnesium bromide.
Explanation:
The balanced chemical reaction is;
[tex]Cl_2+MgBr_2\rightarrow MgCl_2+Br_2[/tex]
[tex]Cl_2[/tex] is the limiting reagent as it limits the formation of product and [tex]MgBr_2[/tex] is the excess reagent.
According to stoichiometry :
1 mole of [tex]Cl_2[/tex] produces = 1 mole of [tex]MgCl_2[/tex]
Thus 2 moles of [tex]Cl_2[/tex] will produce=[tex]\frac{1}{1}\times 2=2moles[/tex] of [tex]MgCl_2[/tex]
Mass of [tex]MgCl_2=moles\times {\text {Molar mass}}=2moles\times 95g/mol=190g[/tex]
Thus 190 g of magnesium chloride can be produced by reacting 2 moles of chlorine gas with excess magnesium bromide
where did all the elements in the universe come from?
Answer:
Wal-mart XDDDDD
Explanation:
Why are red blood cells red
Red blood cells are red because they contain Haemoglobin
What is a song that gets you in a mood? ;)
Answer:
Uhm- s-- money- feelings- die? But, slowed -w-
Explanation:
the ____metals are in the first column. each of them has full shells, plus one extra electron sitting in a new, outer shell
A) Alkali
B) Alkali Earth
C) Arthropod
Answer:
The answer is A.
Explanation:
In periodic table, group 1 (1st column) are Alkali metals and group 2 (2nd column) are Alkali Earth metals.
HELPPPP I NEED TO SEND THEM TO MY TEACHER ITS REACTIONS AND SOME OF THEM MIGHT CANT HAPPEN
Answer:
Explanation:
follow the rule of "a weak acid can't make a stronger acid and weak base can't make a stronger base(it's pretty accurate for acid/salt reactions/replacemnts)" the last reactions won't work, but the second to last one will be kbr+pb(no3)2-> kno3 + PbBr2 (this is unballanced.) the first reaction will work. the second one i'm not too sure tbh, but i think it won't work since barium hydroxide's a weak base and if it were to react it would make koh, a super strong base
Answer:
3Ba(OH)2 + 2K3PO4 ----> 6KOH + Ba3(PO4)2
2KBr + Pb(NO3)2 ------> 2KNO3 + PbBr2
H3PO4 + 3KCl -----> K3PO4 + 3HCl
Explanation:
Which of the following examples is a chemical property?
Answer:
Examples of chemical properties include flammability, toxicity, acidity, reactivity (many types), and heat of combustion. Iron, for example, combines with oxygen in the presence of water to form rust; chromium does not oxidize (Figure 2).
Explanation: