Which orbital block corresponds to the transition metals in the periodic table?

Answers

Answer 1
On the periodic table, the orbital blocks are broken up based on section. The first two rows (Alkali Metals, Alkaline Earth Metals) are the S block, the transition metals are the D block, the nonmetals/metalloids are the P block, and the extra elements at the bottom of the periodic table are the F block. Therefore, the answer would be “The D block”. Hope this helped!

Related Questions

Please use the below balanced equation to answer this question.    2H2(g)  +  O2(g)  ->   2H2O(l) How many grams of water will be produced if I have 83.4 liters of oxygen gas at STP?
A) 48.65 grams H2O
B) 65.78 grams H2O
C) 85.71 grams  H2O
D) 134.18 grams H2O

Answers

At STP (standard temperature and pressure conditions), 1 mol of any gas occupies 22.4 L 
This rule is applied to O₂
22.4 L volume occupied by 1 mol
Therefore 83.4 L occupied by - 1/ 22.4 x 83.4 = 3.72 mol
stoichiometry of O₂ to H₂O is 1:2
then the number of moles of water produced - 3.72 mol x 2= 7.44 mol
mass of water produced - 7.44 mol x 18.01 g/mol = 134.1 g
correct answer is D

Compare and contrast the properties of acids and bases. include two similarties and two differences.

Answers

Hello!

Similarities:

-They can conduct electric current because they both are ionic substances.-

-They both form Water and Salt when neutralized. 

Differences:

-Acids release Hydronium ions (H₃O⁺) when hydrolyzed while Bases release Hydroxyl ions (OH⁻) when hydrolyzed. 

-Acids are commonly formed with non-metals (such as Chlorine, Sulfur, Oxygen, and Nitrogen) while Bases are commonly formed with metals (such as Sodium, Potassium, Calcium, and Copper). 

Have a nice day!


Final answer:

Acids and bases are similar in that they conduct electricity in aqueous solutions and both react to form salt and water. Their differences lie in taste, color changes in litmus paper, and pH values where acids have pH lower than 7 and bases have pH greater than 7.

Explanation:

Acids and bases are both types of compounds that chemists often deal with. They are similar in that they both conduct electricity when in aqueous solution and they both react with each other to form salt and water, a reaction known as neutralization. However, they are also distinctly different. The first difference is that acids have a sour taste and can turn blue litmus paper red, while bases have a bitter taste and can turn red litmus paper blue. Additionally, acids tend to have a pH less than 7, whereas bases have a pH greater than 7.

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The activation energy for the reaction no2(g)+co(g)⟶no(g)+co2(g) is ea = 175 kj/mol and the change in enthalpy for the reaction is δh = -200 kj/mol . what is the activation energy for the reverse reaction?

Answers

Final answer:

The activation energy for the reverse reaction of NO2(g) + CO(g) → NO(g) + CO2(g) is 375 kJ/mol. This is calculated using the formula that subtracts the change in enthalpy from the activation energy of the forward reaction.

Explanation:

The activation energy for the reverse reaction can be determined using the concept that the activation energy for a reaction and the activation energy for the reverse reaction must total the energy difference between the reactants and the products, which is given by the change in enthalpy (ΔH). The given forward reaction NO2(g) + CO(g) → NO(g) + CO2(g) has an activation energy (Ea) of 175 kJ/mol and a change in enthalpy (ΔH) of -200 kJ/mol.

To find the activation energy for the reverse reaction, we use the formula:

Activation energy of reverse reaction = Activation energy of forward reaction - ΔH

Plugging in the values we get:

Activation energy of reverse reaction = 175 kJ/mol - (-200 kJ/mol)

This calculation yields an activation energy for the reverse reaction of 375 kJ/mol.

Which statement describes the periodic law?
Metals are both good conductors of heat and electricity.
Atomic masses always increase across a period.
Nonmetals are of the most reactive elements.
Elements in the same group have similar chemical properties.

Answers

Answer is: elements in the same group have similar chemical properties.
Periodic law is the arrangement of the elements in order of increasing atomic number.
For example all alkaline metals (I group of periodic table, Na, K, Cs...) loose one electron in chemical reaction and react vigorously with water.

elements is the same group have similar chemical properties

Calculate the number of moles of aluminum, sulfur, and oxygen atoms in 4.00 moles of aluminum sulfate, al2(so4)3. express the number of moles of al, s, and o atoms numerically, separated by commas.

Answers

Answer: 8, 12, 48.


Explanation:


1) Aluminum:


There are 2 atoms of Al in the unit formula Al₂(SO₄)₃, so there are 4x2 = 8 atoms of Al in 4 unit formulas of the same compound.


2) Sulfur:


There are 3 atoms of S in the unit formula Al₂(SO₄)₃, so there are 4x3 = 12 atoms of S in 4 unit formulas of the same compound


3) Oxygen:


There are 4x3 = 12 atoms of O in the unit formula Al₂(SO₄)₃, so there are 4x12 = 48 atoms of O in 4 unit formulas of the same compound.


So, the answer is 8, 12, 48

The number of moles of aluminum, sulfur, and oxygen atoms in 4.00 moles of aluminum sulfate, Al₂(SO₄)₃ are 8.00, 12.00, and 48.00, respectively.

Aluminum: There are 2 aluminum atoms in each molecule of aluminum sulfate. So, in 4.00 moles of aluminum sulfate, there are 2 x 4.00 = 8.00 moles of aluminum atoms.

Sulfur: There is 1 sulfur atom in each molecule of aluminum sulfate. So, in 4.00 moles of aluminum sulfate, there are 1 x 4.00 = 12.00 moles of sulfur atoms.

Oxygen: There are 12 oxygen atoms in each molecule of aluminum sulfate. So, in 4.00 moles of aluminum sulfate, there are 12 x 4.00 = 48.00 moles of oxygen atoms.

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The diagram represents wavelengths of different colors of visible light that pass by in a specific time period.

Answers

The question is Which color of light has the greatest frequency?
the answer is Violet.
White light is a combination of all colors of in the color spectrum, that is it has all the colors of the rainbow. Combining primary colors of light like red, blue, and green creates secondary colors such as yellow, violet among others. One end of the spectrum is red light, with the longest wavelength and lowest frequency, while on the other end there is violet color with the shortest wavelength and the greatest frequency.

Answer:

Violet

Explanation:

A species that changes the rate of a reaction but is neither consumed nor changed is
A. A catalyst.
B. An activated complex.
C. An intermediate.
D. A reactant.

Answers

A catalyst i think is the answer

A. A catalyst!!!


Hope it Helps!!!


atoms with 5 valence electrons usually form how many bonds?,

Answers

Atoms with 5 valence electrons usually form 3 bonds. This is because for an atom to have a complete octet, atoms want to have 8 electrons in their outer shell. Because the atom currently only has 5 electrons in its outer shell, it will want to form 3 new bonds in order to have a total of 8 valence electrons.

Write a balanced symbol equation for the complete combustion of propanol

Answers

2C3H7OH+9O2→6CO2+8H2O

I hope it helped you!

Two or more atoms of different elements covalently bonded together are referred to as __________.

Answers

The answer is molecular compound. Their main difference with ionic compounds is that the atoms of the two elements in a molecular compound are covalently bonded while an ionic compound, the different atoms are ionically bonded.  Examples of molecular compound are sulfur dioxide and carbon tetrachloride. Atoms in molecular compounds are held together through sharing of electrons while atoms in ionic compounds are held together by electrostatic forces




Answer: molecular compound.


Justification:


1) The chemical combination of two or more different elements is called compound. Each compound has a unique composition and specific properties, which make it different from the elements (atoms) of which it is constituted.


2) The chemical union is called chemical bond. The chemical bonds between elements can be matallic bonds, ionic bonds, or covalent bond.


3) The metallic and ionic bonds do not lead to proper molecules because the structure is continuos.


4) The covalent bonds lead to units named molecules. Some examples of molecular compounds are; CH4, C2H6, C3H8, C4H10.

What is the value of ∆G in a spontaneous reaction?


less than 0



greater than 0



equal to 0



equal to 1

Answers

I believe the answer is >0, but it could be <0

What is the molar mass of BF3

Answers

In Chemistry, the Periodic Table is the source of all knowledge. Look on it for the information you need.
B = 11 grams / mol
F = 19 grams / mol
This stuff has a formula of BF3.
The 3 only affects the F. There is 1 Boron and 3 florines. If you want a number to affect the Boron, use brackets. In this case, we don't.
BF3 = 11 + 3*19 = 11 + 57 = 68 grams / mol

Molar Mass BF3 = 68 grams /mol <<<< ==== answer


In order to reproduce, many flowering plants use external agents, such as insects or birds, to aid in the pollination process. What function do the color and odor of the flowers provide for the flowering plants?
A.
They help the plant feel happy and confident.
B.
They attract birds and insects which aid in the pollination process.
C.
They scare off larger animals that eat plants.
D.
They keep the pollinating insects from eating the plants.

Answers

The insects, birds, etc. are called pollinators. Because they help in pollination. The flowers attract birds and insects which aid in the pollination process. The correct option is B.

What is pollination?

The process in which the pollen grains are transferred from the anther to the stigma of flowers is defined as the pollination. The agents which are responsible for the pollination are pollinators.

The flowers use scent to attract pollinators. A signal which helps the pollinators to find the particular flower is known as the scent. These floral scents are known to be a complex mixture of highly volatile compounds and essential oils that is emitted by the flowers into the atmosphere.

A flower scent's structure, color, and odor are the important factors which attract the pollinators. Those plants pollinated by bees and flies have sweet scents and those pollinated by beetles have fruity odors.

Thus the correct option is B.

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How many grams of CO2 are in 6 mol of the compound (this is a science question)? and the units?

Answers

n(CO₂) = 6 mol.
M(CO₂) = 12 g/mol + 2 · 16 g/mol.
M(CO₂) = 44 g/mol.
m(CO₂) = n(CO₂) · M(CO₂).
m(CO₂) = 6 mol · 44 g/mol.
m(CO₂) = 264 g.
n(CO₂)- amount of substance of carbon dioxide.
m(CO₂) - mass of carbon dioxide.
M(CO₂) - molar mass of carbon dioxide.

What is the term for a type of reaction in which an acid and a base react to produce a salt and water?

Answers

neutralization 
is the probable answer, which I don't know how to explain, but I know that's the answer because I learned about it a few years ago and I'm pretty smart. =]

sodium bicarbonate reacts with sulfuric acid to form sodium sulfate, carbon dioxide, and water. calculate the mass od sodium bicarbonate necessary to produce 1.75 g of carbon dioxide gas.

How would i even go about doing this?,

Answers

Obtain molar mass of CO2 and NaHCO3 Mass of CO2 divided by molar mass of CO2 gives moles of CO2.
 You have 2 moles of CO2 at the end and 2 moles of NaHCO3 at the beginning Now You have moles of NaHCO3 multiply molar mass of NaHCO3 by the moles of NaHCO3 to get only mass of NaHCO3 initial.

Which product besides radiation do radioactive atoms give off when they decay?



A.


heat energy


B.


poisonous gases


C.


ridge pushes


D.


p waves

Answers

b. or a. sounds right.                                                                           .                                                                                                        .

The radiations are released in the radioactive decay along with the heat energy. Thus, option A is correct.

What are radioactive atoms?

The radioactive atoms are given as the one that has the presence of unstable nuclei. The unstable nuclei have been giving off radiations that form them to attain stability.

The radioactive atoms have been emitting the radiations from the nucleus to become stable, and the nuclear or the radioactive radiations from the radioactive decay.

The decay of the radioactive elements releases the radiations such as alpha, beta, gamma, and other radiations. The decay along with the release of the radiation releases energy.

Therefore, in radioactive decay, the atoms along with the radiations release heat energy. Thus, option A is correct.

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#1: What is usually released in a combustion reaction?

A. energy

B. elemental oxygen

C. a carbon-based fuel

D. elemental carbon

**my answer; A. energy

is that right?,

Answers

A combustion reaction is when a substance reacts with oxygen and releases energy in the form of light and heat. A combustion reaction will always includes a hydrocarbon and oxygen as the reactants and always produces carbon dioxide and water as products. Therefore your answer of A is correct.

when you discuss calories in food you are talking about kilocalories (Kcal) which is the amount of heat necessary to raise 1000 mL of water by 1 degree Celsius which is approximately 4.18 kJ. compare the number of Kilocalories in one gram of tomatoes to the number of Kilocalories in one gram of corn chips

Answers

100 g of corn chips has 17.69 calories

1 g of corn chips has 17.69/100 or 0.1769 calories

Therefore, 1 g of tomatoes has 0.1769 x 10⁻³ kilocalories

100 g of corn chips has 518 calories

1 g of corn chips has 518/100 or 5.18 calories

Therefore, 1 g of corn chips has 5.18 x 10⁻³ kilocalories

The main source of phosphorous is in: rocks water plants the atmosphe

Answers

Answer:

rocks

Explanation:

Answer:

Rocks

Explanation:

Marco wants to investigate the chemical properties of sodium bicarbonate, or baking soda. He plans to carry out the tests below.

Test 1: Mix a teaspoon of sodium bicarbonate into a cup of warm water to see if it dissolves.

Test 2: Mix a teaspoon of sodium bicarbonate into a cup of vinegar to see if it fizzes.

Test 3: Heat a teaspoon of sodium bicarbonate in the oven to see if its melting point is less than 400 degrees Fahrenheit.

Which statement provides the best assessment of his tests?

Only Test 3 will indicate a chemical property of sodium bicarbonate. Tests 1 and 2 will show a physical property of the substance.

Only tests 1 and 2 will indicate chemical properties of sodium bicarbonate. Test 3 will show a physical property of the substance.

Only Test 2 will indicate a chemical property of sodium bicarbonate. Tests 1 and 3 will show a physical property of the substance.

Only tests 1 and 3 will indicate chemical properties of sodium bicarbonate. Test 2 will show a physical property of the substance.

Answers

Answer is: Only Test 2 will indicate a chemical property of sodium bicarbonate. Tests 1 and 3 will show a physical property of the substance.
Solubility in water and melting point of substance are physical property. In test 2 there is chemical property (chemical reaction):
NaHCO₃ + CH₃COOH → H₂O + CO₂ + CH₃COONa.

Answer:

Only Test 2 will indicate a chemical property of sodium bicarbonate. Tests 1 and 3 will show a physical property of the substance.

Explanation:

1) In test 1 we are dissolving sodium bicarbonate and here there is no chemical change in the property of sodium bicarbonate if it dissolved so it is a pure physical process.

2) In test 2 we are reacting sodium bicarbonate with vinegar (acetic acid).

The reaction is:

[tex]NaHCO_{3}+CH_{3}COOH--->CH_{3}COONa+H_{2}O+CO_{2}[/tex]

Due to formation of carbon dioxide it fizzes. Thus this is a chemical property of sodium bicarbonate to acts as base.

3) In test 3, we are heating and testing the melting point of sodium bicarbonate, which is again a physical property.

What motivated arrhenius to calculate how changes in carbon dioxide might affect the climate?

Answers

Arrhenius was seeking to understand the causes of ice ages. 
He was the first to use basic principles of  physical chemistry to calculate estimates of the extent to which increases in atmosphere carbon dioxide increases Earth's surface temperature through the Arrhenius effect. Arrhenius's paper was the first to quantify the contribution of carbon dioxide to the greenhouse effect and to speculate whether variations in the atmospheric concentration of carbon dioxide have contributed to long-term variations in climate.

#1: Martha has a large amount of 1.25 M H2SO4 in her lab. She needs 36 grams of H2SO4 for a chemical reaction she wants to perform. How many liters of the solution should she use?

A. 2.9 L

B. 5.8 L

C. 0.58 L

D. 0.29 L

***my answer: D. 0.29 L

is that right? @chmvijay :),

Answers

Yes, that is correct. There are 1.25 moles in one liter of solution, and there are about 98 grams in one mole of H2SO4. Using this information we can readily eliminate A and B as answers, as there would be far more than 36 grams in 2.9 and 5.8 liters of this solution. 98 x 1.25 = 122.5 grams of H2SO4 in one liter, and we can then divide 36 into 122.5 to arrive at 0.29L.

Answer:

D. 0.29 L

Explanation:

To calculate the required volume, we can convert the concentration of the solution from M to g/L, keeping in mind the molar mass of H₂SO₄, 98 g/mol :

1.25 [tex]\frac{mol}{L}*\frac{98g}{1mol}=[/tex]122.5 g/L

So a concentration of 1.25 M of H₂SO₄ is the same as a concentration of 122.5 g/L.

Finally we divide 36 grams by the concentration:

[tex]\frac{36g}{122.5g/L}[/tex] = 0.29 L

So your answer was correct, it is option D.

What element is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p65s2 4d10 5p4?

Answers

Final answer:

The element with the electron configuration 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p4 is Tin (Sn). This is found by adding up the electrons in each part of the configuration.

Explanation:

The electron configuration provided, 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p4, represents the element Sn, or Tin in the periodic table. The configuration corresponds to the distribution of electrons among different energy levels (shells) and sub-levels in an atom. To identify the element, we add up the electrons represented by each part of the configuration (e.g., s2 implies 2 electrons, p6 implies 6 electrons etc.). We see that the total number of electrons is 50, which corresponds to the atomic number of Tin (Sn) in the periodic table.

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Consider the reaction: 2A(g)+B(g)→3C(g). When A is changing at a rate of -0.110M⋅s−1, How fast is C increasing?

Answers

From the reaction above, the rate is given by the following formula:
r = -(1/2) dA / dt = - dB / dt = (1/3) dC/ dt
Note that A and B charge is negative due to they decrease with time
given dA / dt = -0.110 M/s
hence dB / dt = -0.110 / 2 = -0.055 M/s
dC / dt = (-3/2) (-0.110) = 0.165 M/s 

Using the equation 2H2 + O2 --> 2 H2O, if 192 g of O are produced, how many grams of hydrogen must react with it? Help me understand how to do this?

Answers

To produce a molar conversion, you need to know the molar mass of each molecule. I presume you mean there are 192 grams of O2. The molecular weight of oxygen is 16 g/mol. Therefore, O2 is 32 g/mole.

   If there are 192 grams of O2, then:
 192 grams x (1 mole/32g) = 6 moles of O2.

   To react each mole of oxygen, you need 2 moles of hydrogen (H2). You can see this in the equation 2H2 + O2 --> 2 H20.
   To react 6 moles of O2, you need 12 moles of H2.
   Now that we have the total moles of hydrogen needed, we now use the molar mass of H2 (2 grams/mole)
   12 moles H2 x (2 grams/1 mol H2) = 24 grams of H2.

Which Of the following compounds is an electrolyte?
a)rubbing alcohol
b)sugar
c)silicon dioxide
d)sodium hydroxide

Answers

Hello,

Here is your answer:

The proper answer to this question is option D "sodium hydroxide".

Here is how:

Sodium Hydroxide its a white substance that is a electrolyte.

Your answer is D.

If you need anymore help feel free to ask me!

Hope this helps!

The typical carbon atom is described in the periodic table by the accompanying box. how many neutrons are in a typical carbon atom?

Answers

Six protons and Six Neutrons

How do you balance this chemical equation?

barium chlorate --> barium chloride + oxygen

I'm really confused on this question because it contains some ionic compounds. How would you balance it? Thanks!,

Answers

Ba(ClO3)2 --> BaCl2 + 3 O2

The fact that there are some ionic compounds doesn't matter. Just use the formulas.
barium chlorate = Ba(ClO3)2
barium chloride = BaCl2
Oxygen = O2

Now create the unbalanced equation
Ba(ClO3)2 --> BaCl2 + O2


And balance in the usual fashion. Count the atoms of each element on both sides
Ba = 1, 1
Cl = 2, 2
O = 6, 2

And oxygen is out of balance. But can be easily handled with a 3 coefficient on the right hand side. So:
Ba(ClO3)2 --> BaCl2 + 3 O2

And we have a balanced equation.

To balance the equation for the decomposition of barium chlorate into barium chloride and oxygen, ensure that there are equal numbers of each atom on both sides of the equation. The balanced equation is 2 Ba(ClO₃)₂ → 2 BaCl₂ + 3 O₂.

To balance the chemical equation for the decomposition of barium chlorate into barium chloride and oxygen, we must ensure that the number of each type of atom is the same on both sides of the equation. The formula for barium chlorate is Ba(ClO₃)₂, barium chloride is BaCl₂, and oxygen is O₂ (since oxygen is a diatomic molecule).

The unbalanced equation is as follows:

Ba(ClO₃)₂ → BaCl₂ + O₂

To balance this equation:

First, balance the oxygen atoms. There are 6 oxygen atoms on the reactant side (from two chlorate ions) and 2 on the product side (one O₂ molecule). Place a coefficient of 3 in front of the O₂ to balance the oxygen atoms.Now, check the barium and chlorine atoms. Each side has one barium atom and two chlorine atoms, so they are already balanced.

The balanced equation is:

2 Ba(ClO₃)₂ → 2 BaCl₂ + 3 O₂

A force has to push the bug forward. Identify this force. How does the bug produce it?

Answers

Hi there!

This force is kinetic energy. The bug generates this force by using energy to move its leg(s), making it move forward. The origin of the energy comes from the food that the bug eats. The food is then turned into calories (energy) and stored as potential energy before the bug uses it as kinetic energy. 

Hope this helps!
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