The electron configuration of an element is 1s22s2. How many valence electrons does the element have? (1 point) a 1 b 2 c 3 d 4

Answers

Answer 1

Answer:

b

Explanation:the shell is 2 so ignore the 1s electrons it is only the level 2 electrons that are valence


Related Questions

What is always conserved in both physical and chemical changes, explain?

Answers

All chemical reactions are chemical changes. The Law of Conservation of Matter states that matter cannot be created or destroyed. In a physical change, substances can change form, but the total mass remains the same. In a chemical change, the total mass of the reactants always equals the total mass of the products.

how many moles are in 6.31x10^24 C atoms

Answers

Answer:

Explanation:

1 mol of any chemical is 6.02 * 10^23

x mol of any chemical is 6.31 * 10^24

You should look at this before you put it in  your calculator. You should think roughly 10.

Now you can set it up as a proportion

1/x = 6.02 * 10^23/6.31 * 10^24        Cross multiply

6.02 * 10^23 x = 1 * 6.31 * 10^24      Divide by 6.02 * 10^23

x = 6.31 * 10^24 / 6.02 * 10^23

x = 10.48 mols.

It should be 10.48 mols

How many atoms of nitrogen appear to be on the reactant side?

Answers

I believe the answer it 2

What would the name of the following compound be:

Answers

Answer:

ammonium phosphite

How many grams of calcium phosphate does 4.1*10^25 have

Answers

Answer:

310.176722 grams

You can view more details on each measurement unit: molecular weight of Calcium Phosphate or grams The molecular formula for Calcium Phosphate is Ca3(PO4)2. The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles Calcium Phosphate, or 310.176722 grams.

How do CFC’s illustrate that technical advances can be a “double-edged” sword?

Answers

Answer:

CFC’s illustrate that technical advances can be a “double-edged” sword as CFC's were made for the advantages but soon or later it came as a disadvantage for environment.

CFC's was discovered with many advantages such as they are stable, non-corrosive, and replacement of harmful ammonia used in refrigerators  and air conditioning systems. But soon it is also discovered that CFC's are destroying  the upper atmosphere layer called ozone, which is a very big disadvantage for us. CFCs are major contributor  to global warming after carbon dioxide.

Hence, it proves that CFC’s shows how technological advancement can be “double-edged” sword.

A class has compiled this list of examples of artificial selection.
• The development by dog breeders of a variety of
poodles that have different coats that do not require
brushing
The crossbreeding of cows that have provided meat and
milk for humans for many centuries
• The breeding of domestic turkeys that have large
amounts of breast meat and a reduced wing size that
makes them unable to fly
• The creation of varieties of apples that remain crisp
throughout the winter but have less flavor
• The development of roses that will wilt quickly and have
long stems, no thorns, and no strong scent
Which three statements describe the common characteristics of all of the
examples of artificial selection?
Da
Db
c.
Artificial selection always requires a detailed knowledge of the genetic makeup of a species and a familiarity with the mathematics
of inherited traits.
Artificial selection infers that a species experiences natural genetic mutation rather than reproduction planned by humans.
Artificial selection involves enhancing the natural characteristics of a species through planning and coordination of its breeding.
Artificial selection has been practiced in many forms for centuries to improve crops and livestock
Artificial selection may have unintended consequences that can reduce the benefits of a species to humans or limit its function
Do
Oe

Answers

Answer:

the answer is d

Explanation:

Artificial selection may have unintended consequences that can reduce the benefits of a species to humans or limit its function. Therefore, the correct option is option D.

What is artificial selection?

Growing and rearing livestock and plants for human use was one of the greatest important milestones in the advancement of the human species. Techniques have been developed over time to increase crop yields and generate animals with the best qualities. It is known as artificial selection. These beneficial characteristics gradually take over the population.

Artificial selection refers to the selective breeding practises used by humans to select for desirable qualities in organisms and pass those traits on to their offspring. Artificial selection may have unintended consequences that can reduce the benefits of a species to humans or limit its function.

Therefore, the correct option is option D.

To know more about artificial selection, here:

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please help
find the percent composition of Li2O , round to the tenths place

Answers

the percent composition is 100


Could someone please help me? You can ignore number 3

Answers

For Number 2)

THE ELEMENTS TEND TO FORM COMPOUNDS BECAUSE AOMS ARE UNSTABLE AND CAN SHARE ELECTRONS IN THIER OUTER ENERGY LEVELS .

AS WE KNOW, ATOMS OF AN ELEMENT BECOMES MORE STABLE BY LOSING , GAINING AND SHARING ELECTRONS.

Elements react with each other to complete their octet or duplet so as to become stavle in nature. For e.g. Carbon reacts with oxygen to form carbon dioxide. Carbon reacts with four molecules of hydrogen to form methane - CH4.

What volume (in L) of water vapor will be

produced from the reaction of 4.95 L of ethane

(C2He)?

2C2H6(g) + 702(9) — 4CO2(g) + 6H2O(g)

Answers

Answer:

14.85L of water are produced

Explanation:

Based on Avigadro's law, the volume is directly proportional to the moles of a gas.

Based on the equation:

2C₂H₆(g) + 7O₂(g) → 4CO₂(g) + 6H₂O(g)

2 moles of ethane produce 6 moles of H₂O.

Using Avogadro's law: 2L of ethane produce 6L of H₂O.

The addition of 4.95L of ethane are:

4.95L ethane * (6L H₂O / 2L C₂H₆) =

14.85L of water are produced

If you have 15g of sodium carbonate, what
mass of sodium is present in that sample?

Answers

Answer: 6.75 g

Explanation:


How can we use the study of genetics to help determine traits in organisms? Your answer must be in three complete sentences

Answers

Answer:

Genetics is the scientific study of inherited variation. Human genetics, then, is the scientific study of inherited human variation.

Why study human genetics? One reason is simply an interest in better understanding ourselves. As a branch of genetics, human genetics concerns itself with what most of us consider to be the most interesting species on earth

What is a measurement of the electromagnetic field’s alignment?

Answers

Answer:

Explanation:

Magnetic fields can be measured in various ways. If this device, called a dip meter, is first aligned in the direction of the magnetic meridian as defined by a compass, the needle lines up with the total field vector and measures the inclination angle I

Anna notices that different types of clothing stick together when they are dried in an electric dryer. When the clothes are pulled apart, they make sparks and a crackling sound due to electric forces of attraction. How can Anna reduce the amount the clothing clings together in the dryer?

Add a substance to the wash that reduces the number of charges transferred.
Increase the temperature of the air in the dryer to weaken the electric forces.
Dry more clothes at the same time so that there is less room for electric forces.
Change the charges on the clothes by running the dryer at a faster speed.

Answers

Answer:

A: Add a substance to the wash that reduces the number of charges transferred.

Explanation:

The attraction between opposite charges make the clothes attract together. To reduce them Increase the temperature of the air in the dryer to weaken the electric forces. Hence, option A is correct.

What is electric dryer?

An electric dryer is used to dry the clothes and hair or other substances using electric current. A substance can have both negative and positive charges. The opposite charges will attract together while the negative charges repel.

By exposing clothes to electric dryer it will gain electrons from the dryer and the positive poles of the clothes will attracts it. The electric current from the dryer will make clothes temporarily polarised.

If temperature increases, the intermolecular force of attraction decreases by making the kinetic energy of molecules raised. Therefore by increasing the temperature of air from the dryer the attraction can be reduced.

To find more on electric charges, refer here:

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help me pleaseeeeeeeeeeeeeeeeeeeeeeeeee

Answers

Carbon dioxide
Is what it should be

Answer: nitrogen

Explanation:

what are the roles of the mucous select two options PLEASE HELP​

Answers

Answer:

The answer is A and C

CO2
+
NaOH
<=>
NaHCO3
Balance

Answers

Answer:

Explanation:

It is balaned

Left side

1 Na

1 C

3 Os

1 H

=========

Right side

1 Na

1 H

1 C

3 Os

Answer:

CO2 + NaOH = NaHCO3 and the reaction type is synthesis ( this was already balanced)

Explanation:

I took out the  <> to get CO2 + NaOH = NaHCO3

CO2- molar mass= 44.0095

NaOH- molar mass= 39.99710928

NaHCO3- molar mass= 84.00660928

List the phase changes that result of an increase of molecular kinetic energy pls help!! 30 points!

Answers

Answer:

Explanation:

The term change of phase means the same thing as the term change of state. ... i.e. during phase change, the energy supplied is used only to separate the molecules ; no part of it is used to increase the kinetic energy of the molecules. So its temperature will not rise, since kinetic energy of molecules remains the same.

What is the term for electrons that are not held within a bond?

Answers

Answer:

lone pairs. pairs of valence electrons that are not involved in covalent bond formation, unshared pairs of electrons.

Explanation:

I need help knowing if chemical formulas are balanced or unbalanced I cease to understand this ;-;

Answers

Balancing Chemical Formulas is like simple mathematic systems of equations

Lets look at your second example:

H2 + Cl2 = HCl

Lets replace H with x, and Cl with y.

the equation would now be

2x + 2y = xy (now I know in math x+y does not equal xy, but bear with me)

This would not be correct. For the equation to be true, both sides must yield the same counterpart. To do this, you'd have to add a coefficient to balance out both sides.

Looking at the equation, you know you have to balance the right side, as the left side is adding two things up to getting only half value. So, we will add coefficient of "2" to xy. This means that the balanced chemical equation will now be H2 + Cl2 = 2HCl

If you throw a basketball to a friend while you are sitting or standing on a skateboard, what will happen to you when you throw the ball?​

Answers

Answer:

You will more than likely fall or get pushed back a little

Explanation:

Answer

Depends on if you're good on a skateboard or not.

Explanation:

If you're good: Then you wont fall

If you're bad: Then you might fall

Can't tell if this is an actual school question or not, lol

But I hope it helps, :)

Practice working with numbers that have exponents. In the blank provided, write greater than, less than, or equals.

a. 10–2 ____________________ 10–3

b. 10–14 ____________________ 101

c. 10–7 ____________________ 0.0000001

d. 100 ____________________ 101

Answers

Answer:

a. 10⁻² > 10⁻³

b. 10⁻¹⁴ < 10¹

c. 10⁻⁷ = 0.0000001

d. 100 > 10¹

Explanation:

a. 10⁻² > 10⁻³

We can rewrite those numbers as 0.01 and 0.001. That way the answer becomes clearer.

b. 10⁻¹⁴ < 10¹

Any positive number with a negative exponent will be less than 1.

c. 10⁻⁷ = 0.0000001

In the decimal, the 1 is exactly 6 zeros away from the dot, meaning the 1 is in the seventh place.

d. 100 > 10¹

10¹ is equal to 10.

which electrons in an atom have the highest energy level

Answers

Valence electrons hope this helps

Which location of the moon relative to the sun and earth may produce a lunar eclipse?
A) A
B) B
C) C
D) D

Answers

The answer is A - earth shadow cast in moon

Answer:

Its just C

Also because its infront of the sun

If a sample of gas has a volume of 200 ml at a pressure of 700 mm Hg. What will be its pressure if its volume is reduced to 100 ml?

Answers


Meave60
Nov 19, 2015
The new pressure will be
1000 L
, rounded to one significant figure.
Explanation:
Boyle's law states that when a gas is held at a constant temperature and mass in a closed container, the volume and pressure vary inversely. The equation to use is
P
1
V
1
=
P
2
V
2
.
Given
V
1
=
200
mL
×
1
L
1000
mL
=
0.2 L

P
1
=
700 mmHg

V
2
=
100
mL
×
1
L
1000
mL
=
0.1 L

Unknown
P
2

Equation
P
1
V
1
=
P
2
V
2

Solution
Rearrange the equation to isolate
P
2
and solve.
P
2
=
P
1
V
1
V
2

P
2
=
(
700
mmHg
×
0.2
L
)
0.1
L
=
1400 L
, which must be rounded to
1000 L
because all of the measurements have only one significant figure.

Write a detailed diagram about Mountain Vesuvius, labeling important features about it.

Answers

Answer:

Explanation:

Mount Vesuvius is considered to be one of the most dangerous volcanoes in the world because of its proximity to the city of Naples and the surrounding towns on the nearby slopes. The volcano is classed as a complex stratovolcano because its eruptions typically involve explosive eruptions as well as pyroclastic flows

If 5.3 moles of magnesium phosphate react with excess sodium chloride how many moles of magnesium chloride will be formed?

Answers

Answer:
154.0831 g
Explanation:
The formula for the calculation of moles is shown below:

Given: For
Given mass = 41.0 g
Molar mass of = 24.31 g/mol
Moles of = 41.0 g / 24.31 g/mol = 1.6865 moles
Given: For
Given mass = 175 g
Molar mass of = 162.2 g/mol
Moles of = 175 g / 162.2 g/mol = 1.0789 moles
According to the given reaction:

3 moles of Mg react with 2 moles of
1 mole of Mg react with 2/3 moles of
1.6865 mole of Mg react with (2/3)*1.6865 moles of
Moles of = 1.1243 moles
Available moles of = 1.0789 moles
Limiting reagent is the one which is present in small amount. Thus, is limiting reagent. (1.0789 < 1.1243)
The formation of the product is governed by the limiting reagent. So,
2 moles of gives 3 moles of magnesium chloride
1 mole of gives 3/2 moles of magnesium chloride
1.0789 mole of gives (3/2)*1.0789 moles of magnesium chloride
Moles of magnesium chloride = 1.61835 moles
Molar mass of magnesium chloride = 95.21 g/mol
Mass of magnesium chloride = Moles × Molar mass = 1.61835 × 95.21 g = 154.0831 g

1.) What is the maximum number of grams of liquid water at 10C that can be heated to
30C by the addition of 84 joules of heat?

Answers

Answer:

m = 1 gram

Explanation:

Given that,

Heat, Q = 84 J

The temperature increases from 10°C to 30°C.

We need to find maximum number of grams of liquid water. We know that the heat required is given by :

[tex]Q=mc\Delta T[/tex]

c is specific heat of water, c = 4,200 J/kg°C

Use the above formula to find m. So,

[tex]m=\dfrac{Q}{c\Delta T}\\\\m=\dfrac{84}{4,200\times (30-10)}\\\\m=0.001\ kg[/tex]

or

m = 1 gram

So, the required mass is 1 gram.

Which statement describes Sparta’s strategy for the Peloponnesian War?

Sparta used its navy to attack Athens along the coastline.
Sparta ruined Athens’s farmland to try to get Athens to fight on land.
Sparta sailed around the peninsula to attack Athens from two sides.
Sparta attacked Athens directly and attempted to knock down the walls.

Answers

Answer:

it is the  Sparta ruined Athens’s farmland to try to get Athens to fight on farm land

Explanation:

just did

Answer:

the answer is B

Explanation:


Turgor pressure can help plants move. Internal water pressure can cause -

Answers

Answer: Turgor pressure can help plants move. Internal water pressure can cause a wilted stem to return to an upright position.

Hope this helps(:
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PLEASE HELP ME EXPLAIN THESE QUESTIONS IT'S FOR ANATOMY AND PHYSLets put the information you just learned into practice: perform a respiration check on a partner who is at least 12 years old. You may, as recommended by the sites, sneak the respiration check while checking their pulse as long as your partner has consented for you to check their vital signs. Telling someone you are checking their pulse, but instead are planning to check their respiratory rate, would be unethical. Based on your experiences, answer the following questions. 1.Pretend you are entering the respiration rate into a medical record. How would you record it? 2.Was the subjects respiration rate in a health range? 3.What would be different about detecting an abnormal respiration rate if you were checking the respiration rate of a four year old? 4.Do you think you got an accurate respiration rate? Is there any reason to think the subject might have altered their breathing? 5.What exact steps did you take to measure the respiration rate, including any questions you asked or instructions you gave? 6.How long did you measure for? 7. Which parts of the DRABC acronym deal directly with the respiratory system? 8.Some first-aid practitioners also recommend a secondary assessment, which involves a head-to-toe inspection of the patient. Why would this assessment be important? 9.Under which conditions should CPR be performed? What checks or actions should be performed first? Can someone plz explain me what this button does and Im scared to click it Its like a square and its window 10 why did the Ghandi-Jinnah Talks failed in 1944? What are the first organisms to live within a newly created patch of land called?Give examples Ecology Los estudiantesestudiando la leccin.1estan2estn3son Qu elemento rompe la regla del carcter metlico?Which element breaks the rule of metallic character? How long can blood flow to the brain be interrupted before death occurs? Help plz:)))Ill mark u Brainliest A model of a lighthouse has diameter 8 inches and height 18 inches. If theactual diameter of the lighthouse is 20 feet, find its actual height. It was the jackal Tabaqui, the Dish-licker and the wolves of India despise Tabaqui because he runs about making mischief, and telling tales, and eating rags and pieces of leather from the village rubbish-heaps. They are afraid of him too, because Tabaqui, more than any one else in the jungle, is apt to go mad, and then he forgets that he was ever afraid of any one, and runs through the forest biting everything in his way. Mowglis Brothers, The Jungle Book,Rudyard KiplingWhat is the most important purpose of the narrator in this passage?to tell readers how the wolves feel about Tabaqui and why they feel that wayto tell readers how Tabaqui survives in the jungleto tell readers about an encounter with Tabaquito tell readers why Tabaqui is called the Dish-lickerPassage:It was the jackal Tabaqui, the Dish-licker and the wolves of India despise Tabaqui because he runs about making mischief, and telling tales, and eating rags and pieces of leather from the village rubbish-heaps. They are afraid of him too, because Tabaqui, more than any one else in the jungle, is apt to go mad, and then he forgets that he was ever afraid of any one, and runs through the forest biting everything in his way. Mowglis Brothers, The Jungle Book,Rudyard Kipling I NEED HELP ON THIS QUESTION PLSS. y is inversely proportional to X.When y20, x = 2Work out y when x = 5 A baggage check service charges $4 for the first hour and $1 for each additional hour or fraction of an hour. Which point is NOT included in the graph of this step function? A. (6.9, 10) B. (6.1, 10) C. (6.0, 10) D. (5.9, 9) Two students are using estimation to determine reasonable solutions to the expression 89.1 times 9.3. Katie uses the expression 90 times 10. Amaya uses the expression 89 times 9. Which is the best comparison of the estimates and the actual product? ____________ are calibrated to deliver one fixed volume and are ____________ than ______________. Select one: a. Transfer pipets; less accurate; measuring pipets b. Transfer pipets; more accurate; measuring pipets c. Measuring pipets; more accurate; transfer pipets d. None of these answers is correct. e. Measuring pipets; more precise; transfer pipets Pleaseee helppp answer correctly !!!!!!!!!!!!!!!!!! Will mark Brianliest !!!!!!!!!!!!!!!!!!! find 24+3-(28)3a. Zerob. 1.37c. 13.7d. 1 what is the fraction for The first term of a geometric sequence is 8100 . The common ratio of the sequence is 0.1 .What is the 6th term of the sequence? Write the coordinates of the vertices after a rotation of 180 degrees counterclockwise around the origin.