Answer:
Hi, valence electrons are the number of electrons present in the outermost shells of atoms of elements, they affect how sharing or transfer of electrons takes place when the atoms go into any reaction.
they also determine the oxidation state of the atom.
for example, hydrogen has one electron in its outermost shell. therefore in any reactions it tends to loose that electron or gain one more to become stable.
the reason why elements go into reactions is to become stable (to have a complete duplet or octet structure).
As you know, each shells aside from the first has maximum of 8 electrons. so for a element like chlorine which have 7 electrons in the valence shell will gain one electrons in reactions to become stable(have a complete octet structure)
valence electrons also classifies elements( metal or non-metal)
if an element have 1, 2 or 3 valence electron(s), it is likely to be a metal
if an element have 4 or 5, it can be a non-metal or a metalliod (semiconductor)
if an element have 6 or 7, it is likely to be a non-metal
if an element have 8, it is a noble/inert gas
this also explains why noble gases do not react since they already have a duplet structure, they do not need to go into reaction.
good lucks on your exams.
Answer:
The number of electrons in an atom's outermost valence shell governs its chemical properties. ... This tendency is called the octet rule, because the atoms have eight valence electrons. METALS. The most reactive metallic elements are metals from Group 1 (e.g., Na or K ) or Group 2 (e.g., Mg or Ca )
hope this helps.
What is the chemical formula for dinitrogen monoxide?
А
NO
B
NO
С
2NO2
D
N20
Answer:
N20
Explanation:
Balance the equation by putting the correct number in front of each compound. You can work this out mathematically or by drawing pictures on a piece of paper like the videos.
NH3 --> H2 + N2 ammonia dissolving
Answer:
2NH3 --> 3H2 + N2
Explanation:
It's hard to explain how I got these coefficients but I recommend watching Tyler DeWitt on Youttube. He explains tons of chemistry concepts in an easy and clear way. I always watch his videos when I don't understand something.
I would type in "How to balance chemical equation" by Tyler DeWitt
What is the formula of cell respiration? (In a science equation)
Answer:
Hey mate....
Explanation:
This is ur answer.....
Equation : Cellular Respiration: C6H12O6 + 6O2 → 6CO2 + 6H2O.
Hope it helps u,
Mark me as the brainliest....
FOLLOW ME!!!!
Answer:
C6H12O6 + 6O2 → 6CO2 + 6H2O.
Explanation:
Balance chemical equation Calcium hydroxide + carbon dioxide = calcium carbonate + water
Answer:
yaeh
Explanation:
a)Ca(OH)
2
+CO
2
⟶CaCO
3
+H
2
O
No. of atoms:Ca−1;O−4;H−2;C−1
b)Zn+AgNO
3
⟶ZnNO
3
+Ag
No. of atoms:Zn−1;Ag−1;N−1;O−3.
What is the percent composition of aluminum in the ore bauxite (AI2O3)?
Answer:
Molar mass of Al2O3 = 101.961276 g/mol
This compound is also known as Aluminium Oxide.
Convert grams Al2O3 to moles or moles Al2O3 to grams
Molecular weight calculation:
26.981538*2 + 15.9994*3
Percent composition by element
Element Symbol Atomic Mass # of Atoms Mass Percent
Aluminium Al 26.981538 2 52.925%
Oxygen O 15.9994 3 47.075%
Explanation:
Percent composition by element
Element Symbol Mass Percent
Aluminium Al 52.925%
Oxygen O 47.075%
Which pair of substances would be easy to separate using distillation?
A. Water and alcohol
B. Suger and salt
C. Oil and water
D. Sand and gravel
Answer: A
Explanation:
A mixture of PCl5(g), PCl3(g), and Cl2(g) is in a 1.00 L reaction vessel. The total pressure of the reaction system is 1.40 atm at equilibrium. Then the volume of the reaction vessel is reduced from 1.00 L to 0.50 L and equilibrium is re-established at constant temperature. What is the total pressure of the system at this point?
Answer:
The total pressure immediately after the volume reduction is 2.8 atmospheres
Explanation:
The question parameters are as follows;
The initial volume of the reaction vessel, V₁ = 1.00 L
The initial pressure of the reaction system, P₁ = 1.40 atm
The final volume of the reaction system, V₂ = 0.50 L
With the assumption that the gas mixture behaves as an ideal gas, and the temperature is constant, by Boyle's law we have;
P₁·V₁ = P₂·V₂
Where;
P₁ = The initial pressure in the reaction vessel
V₁ = The initial volume in the reaction vessel
P₂ = The total final pressure in the reaction vessel after the reduction in the vessel volume
V₂ = The final volume in the reaction vessel
∴ P₂ = P₁·V₁/V₂
From which we have;
P₂ = 1.40 atm × 1.00 L/(0.50 L) = 2.8 atm
The total final pressure in the reaction vessel, P₂ = 2.8 atm.
Can you…Balance a chemical equation using the relationships identified?
Answer:
A balanced chemical equation not only describes some of the chemical properties of substances—by showing us what substances react with what other substances to make what products—but also shows numerical relationships between the reactants and the products.
how many moles of sodium will react with water to produce 2.0 mol of hydrogen in the following reaction?
2Na(s) + 2H20(1) - 2NaOH(aq) + H2(g)
Answer: 4.0 moles of sodium will react with water to produce 2.0 mol of hydrogen
Explanation:
The balanced chemical equation is:
[tex]2Na(s)+2H_2O(l)\rightarrow 2NaOH(aq)+H_2(g)[/tex]
According to stoichiometry :
1 mole of [tex]H_2[/tex] is produced by = 2 moles of [tex]Na[/tex]
Thus 2.0 moles of [tex]H_2[/tex] are produced by =[tex]\frac{2}{1}\times 2.0=4.0moles[/tex] of [tex]Na[/tex]
Thus 4.0 moles of sodium will react with water to produce 2.0 mol of hydrogen
True or False: Tsunamis always look like a towering wall of water approaching the beach.
Answer:
false
Explanation:
Answer:
True
Explanation:
they can get up to several hundreds of feet.
Which of the following are decomposition reactions? ch4 (g) + o2 (g) → co2 (g) + h2o (l) cao (s) + co2 (g) → caco3 (s) mg (s) + o2 (g) → mgo (s) pbco3 (s) → pbo (s) + co2 (g)
Answer:
I cant really see the individual problems very well but i hope this helps
Explanation:
Decomposition = one thing -> 2 or more things
Synthesis= 2 or more things -> 1 thing
When describing a solution, which of the following statements are true:
A) one substance is dissolved into another C) requires chemical separation
B) heterogeneous D) always involves the combination of a solid with a
liquid. E) All of these descriptions are true
Answer:
E) All of these descriptions are true
Based on the descriptions in the passage, which scientist proposed a model of the atom that matches the
diagram?
Answer:
J. J. Thomson
Explanation:
This is called the plum pudding model which was proposed by J. J. Thomson.
Help! ASAP! Please on the questions
Answer:
62.15 m (squared)
Explanation:
We know that the Area of the square is 5.5 x 4= 22
so 90 degree to 30 degree is divide by 3
so u divide 22 by 3 and get 7.3 wich is the semi circle thing
now 7.3 x 5.5 = 40.15
22 + 40.15 = 62.15 m (squared)
Look im not really sure but I think this is the answer
Please mark as brainliest
Have a great day, be safe and healthy
Thank u
XD
Answer:
1. The area of the rectangle is 22 but I'm not sure the area of the shape above sorry.
A. 28 m
B. 672 m
Explanation:
A. 6 + 6 + 8 + 8 = 28 or 2(6+8) = (2)14 = 28
B. 28 * 24 = 672
A particular mountain stream is home to a population of salamanders that are red in
color. In the past year, a second population of salamanders that are dark blue in color
moved into the same stream. Scientists researching the stream have recently discovered young salamanders that are red with dark blue patches on their bodies.
What can the scientists conclude from this evidence?
A). The salamanders are suffering from a bacterial disease.
B)..The salamanders are on the verge of becoming extinct.
C). The salamanders undergo asexual reproduction.
D). The salamanders undergo sexual reproduction.
Answer:
D
Explanation:
The salamanders undergo se×ual reproduction.
What is Se×ual reproduction?
This is defined as the production of new organisms by the combination of genetic information of two individuals of different genders.
Thus results in variations in the offsprings produced which us why the Salamanders had different color patches.
Read more about Se×ual reproduction here https://brainly.com/question/815744
i just need an explanation :) so the problem was " what is the mass of 5 molecules of water(H2O) , in grams?" my teacher said the answer is 1.50 x 10^-22 but i dont understand why. why is it not 1.50 x 10^24, why is the exponent negative?
Answer:
Explanation:
The exponent is negative because water molecules are absolutely tiny. You can't see a molecule of water on the palm of your hand with your naked eyes, right? If a the mass of a molecule was 1.50 x 10^24, it'd be HUGE... like absolutely massive (possible the size of your city). Molecules are just tiny, tiny particles
please help
Differentiate between the three systems of rearing pigs.
this is ur answer
plzzz mark me as brainliest
QUESTION 8
DOK 4
Watch later Share
Imagine that an atom of Fluorine (F) can bond with one
of the following atoms. Which one do you think it is
most likely to bond with? Why?
Lithium (Li)
Beryllium (Be)
Boron (B)
Carbon (C)
For more videos,
check out:
Click to answer
ne
T
www.video
chemistry
textbook.com
Youlube
SAVE DRAFT
SUBMIT
13:22 / 16:52
СС
Answer:
Li
Explanation:
F is a strongest electronegative element and it will combine with an element with low electronegativity. From the list provided, the element is Li.
AN ARRANGEMENT OF ELEMENTS INTO ROWS and columns according to similiarties in their properties
Answer:
Periodic table of elements
Explanation:
How are igneous and sedimentary rocks similar? A.They are both formed by erosion. B.They are both formed from cooled lava. C.Heat and pressure can turn them into lava. D.Heat and pressure can turn them into metamorphic rock.
Answer:
D
Explanation:
I learned this last year.
Using the mole ratio, how many moles of NH3 are produced when 0.60 mol of nitrogen reacts with hydrogen in the equation N2 + 3H2 --> 2NH3?
Answer:
1.2 moles of NH3 are produced
PLEASE HELP ILL GIVE BRAINLIEST
What do you think will happen if the experiment from the video kept running? Explain with vocabulary words from the
chapter.tinyurl.com/AMPTE-05
Answer:
Since the temperature of the water made the air hot, i believe that after the video if the experiment continued it would have just made the air a little warmer but not too hot.
Explanation:
80 points to whoever ACTUALLY solves ALL 4!!
It has something to do with boyle’s/charle’s/G-L/Combined Gas Laws
I’m super lost and I’ve been working on this for nearly 2 hours!
Answer:
See Explanations
Explanation:
The Empirical Gas Laws include ...
Boyles Law => P₁V₁ = P₂V₂
Charles Law => T₁/V₁ = T₂/V₂
Gay-Lussac's Law => P₁/T₁= P₂/T₂
Avogadro's Law => V₁/n₁ = V₂/n₂
Combined Gas Law => P₁V₁/T₁ = P₂V₂/T₂
Ideal Gas Law => PV = nRT; R = 0.08206 L·Atm/mol·K
One only needs to learn the 'Combined Gas Law' in that it embodies all of the gas law problems.
Start with a simple table for P, V & T and enter given data. If a variable is not given, assume it is constant. Set up P₁V₁/n₁T₁ = P₂V₂/n₂T₂ and substitute given data. Solve for unknown.
Your Problems:
1. P₁ = 1 Atm P₂ = 3 Atm
V₁ = 300ml V₂ = ?
T₁ = Constant T₂ = T₁
n₁ = Constant n₂ = n₁
P₁V₁/n₁T₁ = P₂V₂/n₂T₂
=> (1Atm)(300ml)/(Constant)(Constant) = (3Atm)(V₂)/(Constant)(Constant)
=> (1Atm)(300ml) = (3Atm)V₂
=> V₂ = (1Atm)(300ml)/(3Atm) = 100ml
2. P₁ = 1 Atm P₂ = ?
V₁ = Constant V₂ = V₁
T₁ = 273K T₂ = 82K
n₁ = Constant n₂ = n₁
P₁V₁/n₁T₁ = P₂V₂/n₂T₂
=> (1Atm)(Constant)/(273K)(Constant) = (P₂)(Constant)/(82K)(Constant)
=> (1Atm)/(273K) = (P₂)/(82K)
=> P₂ = (1Atm)(82K)/(273K)
=> P₂ = 0.3 Atm (1 sig-fig)
3. P₁ = 101.25kPa P₂ = 506kPa
V₁ = 5 Liters V₂ = ?
T₁ = Constant T₂ = T₁
n₁ = Constant n₂ = n₁
P₁V₁/n₁T₁ = P₂V₂/n₂T₂
=> (101.25kPa)(5L)/(Constant)(Constant) = (506kPa)(V₂)/(Constant)(Constant)
=> (101.25kPa)(5L) = (506kPa)(V₂)
=> V₂ = (101.25kPa)(5L)/(506kPa)
=> V₂ = 1.00 Liter
4. P₁ = Constant P₂ = P₁
V₁ = 3.2 Liters V₂ = ?
T₁ = 273°C + 273 = 546K T₂ = 400°C + 273 =673K*
n₁ = Constant n₂ = n₁
*Note => be sure to convert all temps to Kelvin when working empirical gas law problems. K = °C + 273
P₁V₁/n₁T₁ = P₂V₂/n₂T₂
=> (Constant)(3.2L)/(Constant)(546K) = (Constant)(V₂)/(Constant)(673K)
=> (3.2L)/(546K) = (V₂)/(673K)
=> V₂ = (3.2L)(673K)/(546K)
=> V₂ = 3.944 Liters ≅ 3.9 Liters (2 sig-figs)
If 10.0g of powdered iron is heated with 10.0g of sulfur in an open crucible, what is the mass of iron (II) sulfide that is formed? What mass of excess reactant is leftover? The reaction is as follows: Fe+S8–> FeS
Answer:
See Explanation
Explanation:
8Fe + S₈ => 8FeS
Given: 10g 10g
moles 10g/56g/mol 10g/256g/mol
= 0.179mol Fe = 0.039mol S₈
Reduce => divide mole values by respective coefficients; smaller value is Limiting Reactant.
0.179/8 = 0.022 0.039/1 = 0.039
=> Fe is limiting reactant
8Fe + S₈ => 8FeS
Given: 10g/56g/mol 10g/256g/mol
= 0.179mol = 0.039 mol 0.179mol FeS produced
1/8(0.179)mol S₈ used (coefficients are equal,
= 0.022 mol S₈ used => moles Fe = moles FeS)
= (0.039 - 0.022)mol S₈ = 0.179mol FeS
remains in excess =(0.179mol)(88g/mol)
= 0.0166 mol S₈ (excess) = 15.8 g FeS
= (0.0166mol)(256g/mol) (Theoretical Yield)
= 4.26g S₈ in excess
This pizza is a delicious combination of a bread crust, tomato sauce, cheese, and meat. Like all nutritious foods, this pizza provides energy for all of the body's activities. HELP ME PLS
1. Where do you think the energy in each of these four food groups comes from? How confident are you with your prediction?
Answer: pizza crust, Vegetables, Dairy, Meat, and Dairy
Explanation:
The pizza crust is important, not only to deliver those mouthwatering toppings to your anxiously waiting taste buds, but to provide vital nutrients from grains. Vegetables are a common and delicious topping for pizza. These toppings provide an array of nutrients and including multiple servings of vegetables in your diet every day is a necessary part of a healthy lifestyle. If you get meat on your pizza, it is an excellent source of protein. All meat is high in protein and iron, which are necessary to build muscle. Cheese is a good source of the calcium we all need for strong bones and teeth. Cheese is also a good source of protein.
A bread crust contains carbohydrate, vegetables contains vitamins, cheese contain calcium and protein, meat contain protein.
What are nutrients?Nutrients are the substance that makes a body healthy.
Food material contain different nutrients that help in growth of the body.
In pizza, we get all type of nutrients
A bread crust contains carbohydrate which provide energy.
Vegetable contains vitamins to keep the body parts healthy.
Cheese contain calcium and protein which maintain the growth and repairing of the body.
Meat contain protein, good for muscles.
Thus, A bread crust contains carbohydrate, vegetables contains vitamins, cheese contain calcium and protein, meat contain protein.
Learn more about nutrient, here:
https://brainly.com/question/1268939
The picture below shows xylem and phloem vessels, which are tube-
like structures in a plant's roots and stems. Phloem is adapted for
transporting the glucose made during photosynthesis to the roots and
stems.
Phloem
Xylem } Vascular
stem
τρος
Xylem
Phloem
Which function is xylem specifically adapted to perform in plants?
(7.12A)
A
It helps prevent wer loss
B
It transports water from the roots to the leaves
с
It exchanges gases with the atmosphere
D
It captures sunlight for photosynthesis
Answer:
B
Explanation:
it transports water from roots to the leafs
HELP PLEASEEEE!!!!!!!!
Nitrogen (N)) reacts with hydrogen (H) to produce ammonia (NH3). Represent this reaction in terms of:
Particles
b. Moles
C. Mass
Answer:
C the answer is c
Explanation:
ITS C
Can someone help me with the first answer ?
Extra points
Explanation:
I'm pretty sure it's; because of the invention of the microscope, scientists were able to work together to develop the cell theory.
Transferring charge by touching or rubbing is called-
A) charging by contact
B) convection
C) insulation
D) none of these
Answer:
A) Charging by contact
Explanation:
Transfer of heat by direct contact, Heat energy is conducted from the hotter medium to the cooler medium
do i look phat in this dress?
Answer:
Very!
Explanation:
Very phat!