only number 3 please

One mole of an atom of a substance is equal to the  gram molecular mass of the element. Therefore, the correct option is option B among all the given options.

A mole is just a measuring scale. In reality, it's one of the International System of Units' seven foundation units (SI). When already-existing units are insufficient, new ones are created. The levels at which chemical reactions frequently occur exclude the use of grams, yet utilizing actual numbers of atoms, molecules, or ions would also be unclear.

A mole consists of precisely 6.022140761023 particles. The "particles" might be anything, from tiny things like electrons and atoms to enormous things like stars or elephants. One mole of an atom of a substance is equal to the  gram molecular mass of the element.

Therefore, the correct option is option B among all the given options.

To learn more about mole, here:

https://brainly.com/question/15209553

#SPJ6

Answer:

true

Explanation:

Answer:

(a) "l" cant be more than n-1.  n= 3 so l cant be more than 2.

(b) Valid

(c) If l=0, ml can only be 0.

Sb, Antimony, 51 electrons

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p3

paramagnetic 3 unpaired electrons

Explanation:

(a) "l" (lower case L) can be 0, 1, 2 up to n-1.  If n=3, l can be 0, 1, or 2.

(b) This set of quantum numbers is valid.  n can be 1, 2, 3, ...

since n= 2, l can be any number from 0 to n-1 or 0,1

Since l=1, ml can be -1, 0, 1

ms can always be +1/2 or -1/2

(c) ml can only be from -l to +l.  If l=0, ml=0.

If l was 2, ml could be -2, -1, 0, 1, 2

the answer is D) 18 electrons

Answer:

Scanning Objective Lens (4x)

Low Power Objective (10x)

High Power Objective Lens (40x)

Explanation:

Which arrow represents the force of gravity acting upon the car?

✔ B

Which arrow represents the normal force on the car?

✔ A

Which arrow represents the applied force on the car when the driver steps on the gas pedal?

✔ C

Answer:

true

Explanation:

After ice melts into liquid water, you can refreeze it into solid ice if the temperature drops. Freezing and melting are physical changes. The substances produced during chemical changes however cannot easily change back into the original substances.

Answer:

crest

Explanation:

900 mph................

Answer:

a = 0.8 m/s/s

Vav = 45m/s

Explanation:

Vav = [tex]\frac{Vi + Vf}{2\\}[/tex]

Vav = [tex]\frac{10 +80}{2}[/tex]

Vav = 45m/s

a = [tex]\frac{v}{t}[/tex]

a = [tex]\frac{4m/s}{5s}[/tex]

a= 0.8m/s/s

Answer:

a) electron

Explanation:

Answer:

a

Explanation:

i took the test

Answer: Atoms that make up reactants rearrange into new products

Explanation:

A chemical reaction is the process of breaking down the chemical bonds of the reacting substances  which are commonly called as reactants and making new bonds to form new substances commonly called as products.

The products will contain the same atoms as there are in the reactants but the bonds will rearrange to form different substances.

Every chemical reaction is accompanied with absorption or release of energy.

Answer:

IODINE

Explanation:

 The sublevel notation of the element:

      1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁵

To find this element, we must add the powers of the each of the sublevels. This is the number of electrons in the orbital of the atom.

 2 + 2 + 6 + 2 + 6 + 2 + 10 + 6 + 2 + 10 + 5  = 53

  This give atom has 53 electrons and we can assume it to have an atomic number of 53.

The element is IODINE

Answer:

Scientists define temperature with certain rules like the measure of the ability of a substance, or more generally of any physical system, to transfer heat energy to another physical system. The temperature of a substance is closely related to the average kinetic energy of its molecules.

Explanation:

Scientists define temperature as a measure of the average kinetic energy of the particles in a substance. In simpler terms, it reflects how fast the particles are moving within a material.

When an object is heated, its particles gain kinetic energy, leading to an increase in temperature. On the other hand, cooling reduces the average kinetic energy and results in a decrease in temperature.

Temperature is typically measured using various scales, such as Celsius, Fahrenheit, and Kelvin. Kelvin is the most commonly used scale in scientific applications since it is an absolute temperature scale, starting from absolute zero, where particles have minimal kinetic energy.

Learn more about Temperature, here:

https://brainly.com/question/7510619

#SPJ6

Mass : 846.268 g

The mole is the number of particles contained in a substance

1 mol = 6.02.10²³

Moles can also be determined from the amount of substance mass and its molar mass

[tex]\tt mol=\dfrac{mass}{MW}[/tex]  

mass of Al₂O₃ :

MW 101,96 g/mol

mass=mole x MW

[tex]\tt 8.3\times 101.96=846.268~g[/tex]

The volume of the liquid = 8.7 ml

Graduated cylinder is a laboratory tool used to measure the volume of liquid

Also called a measuring cylinder

Each line (marked line) on this cylinder shows a scale that shows the total volume of water.

The reading is based on a curve of the fluid formed called the meniscus. Read the measurement of the amount of fluid at the bottom of the meniscus (the position of our eyes is parallel to the level of the meniscus and the cylinder is located in a flat (not tilted) place

If we look at the picture (attached), the meniscus is located between the scale / line 8.6 and 8.8(interval 0.2 ml), so the volume of the liquid shows the number 8.7 ml

Answer:

B

Explanation:

Answer:

B.

radiant ---> thermal

Explanation:

Mass of K₂SO₄ : 1.75 g

The concentration of a substance can be expressed in several quantities such as moles, percent (%) weight/volume,), molarity, molality, parts per million (ppm) or mole fraction. The concentration shows the amount of solute in a unit of the amount of solvent.

volume of solution = 25 ml

% (m/v)=7%

mass of K₂SO₄ :

[tex]\tt \%m/v=\dfrac{mass~of~solute}{volume~of~solution}\times 100\%\\\\7\%=\dfrac{mass~K_SO_4}{25}\times 100\%\\\\mass~K_2SO_4=7\times 25\div 100=1.75~g[/tex]

Answer:

1.2 × 10²⁴ molecules NH₃

General Formulas and Concepts:

Chemistry

Explanation:

Step 1: Define

34 grams NH₃

Step 2: Define conversions

Avogadro's Number

Molar Mass of N - 14.01 g/mol

Molar Mass of H - 1.01 g/mol

Molar Mass of NH₃ - 14.01 + 3(1.01) = 17.04 g/mol

Step 3: Convert

[tex]34 \ g \ NH_3(\frac{1 \ mol \ NH_3}{17.04 \ g \ NH_3} )(\frac{6.022 \cdot 10^{23} \ molecules \ NH_3}{1 \ mol \ NH_3} )[/tex] = 1.20157 × 10²⁴ molecules NH₃

Step 4: Check

We are given 2 sig figs. Follow sig fig rules.

1.20157 × 10²⁴ molecules NH₃ ≈ 1.2 × 10²⁴ molecules NH₃

Answer:

Mn(IV): 3 outer-shell d electrons

Co(III): 6 outer-shell d electrons

Fe(II): 6 outer-shell d electrons

Ni(II): 8 outer-shell d electrons

Explanation:

Mn(IV):

The ion is Mn⁴⁺, so it has lost 4 valence electrons. The ground state electronic configuration of Mn is [Ar]3d ⁵ 4s ². When the neutral atom loses 4 electrons, the electronic configuration is [Ar]3d ³.

outer-shell d electrons = 3

Co(III):

The ion is Co³⁺, so it has lost 3 valence electrons. The ground state electronic configuration of Co is [Ar]3d ⁷4s ². When the neutral atom loses 3 electrons, the electronic configuration is [Ar]3d ⁶.

outer-shell d electrons = 6

Fe(II):

The ion is Fe²⁺, so it has lost 2 valence electrons. The ground state electronic configuration of Fe is [Ar]3d ⁶4s ². When the neutral atom loses 2 electrons, the electronic configuration is [Ar]3d ⁶.

outer-shell d electrons = 6

Ni(II):

The ion is Ni²⁺, so it has lost 2 valence electrons. The ground state electronic configuration of Ni is [Ar]3d ⁸4s ². When the neutral atom loses 2 electrons, the electronic configuration is [Ar]3d ⁸.

outer-shell d electrons = 8

The d electron in the outer shell of each of the transition metal are:

Mn(IV): 3 d electrons in the outer shell.

Co(III): 6 d electrons.

Fe(II): 6 d electrons.

Ni(II): 8 d electrons.

Electronic configuration is the arrangement of the electrons of an atom.

There are subshell s, p, d, f.

The electrons are arranged in these subshells.

Each element has different arrangement of electrons.

Thus, the number of d electron in each of the element is: Mn(IV) :3, Co(III) :6, Fe(II) :6, Ni(II) :8.

Learn more about electronic configuration

https://brainly.com/question/5524513

Answer:

Elements in the same period have the same number of electron shells.

Explanation:

elements gain electrons and protons and become less metallic

Answer:

Ca2 solid state

H2O liquid state

Ca(OH)2 I believe this would be in solid state

H2 gas state

Explanation:

Answer:

V = 150.49 L

Explanation:

Given data:

Pressure = 0.800 atm

Temperature = 39 °C (39+273 = 312 K)

Moles of gas = 4.70 mol

Volume of gas = ?

Solution:

Formula:

PV = nRT

V = nRT/P

V = 4.70 mol × 0.0821 atm.L/mol.K ×  312 K  / 0.800 atm

V = 120.39 atm.L/  / 0.800 atm

V = 150.49 L

Answer:

For all uncharged atoms, the number of electrons equals the number of protons. The mass number 40 is the sum of protons and neutrons. To find the number of neutrons, subtract the number of protons from the mass number.

Answer:

mass number- protons

Explanation:

Answer:

x=51.66

Explanation:

1 ml = 1 gram

(mass) (Δt) (Cp) = (mass) (Δt) (Cp)

Substituting values into the above, we then have:

(25)(25-x)(4.184)=(50)(x-65)(4.18)

Solve for x

x= 51.6667

The final temperature is "51.67°C".

According to the question,

At 65°C,

= [tex]\frac{50}{50+25}[/tex]

= [tex]\frac{50}{75}[/tex]

= [tex]0.66667[/tex]

At 25°C,

= [tex]\frac{25}{50+25}[/tex]

= [tex]\frac{25}{75}[/tex]

= [tex]0.33333[/tex]

By multiplying the volume fractions, we get

→ [tex]65^{\circ} C\times 0.66667[/tex] = [tex]43.3334^{\circ}C[/tex]

→ [tex]25^{\circ} C\times 0.33333[/tex] = [tex]8.3333325^{\circ} C[/tex]

hence,

The final temperature will be:

= [tex]43.33334+8.333325[/tex]

= [tex]51.6666^{\circ}C[/tex]

or,

= [tex]51.67^{\circ} C[/tex]

Thus the above answer is right.

Learn more:

https://brainly.com/question/13811538

Answer:

619.465 kilometers

Explanation:

1609 m = 1 mile

so 385 miles is equal to 619465 meters (385 x 1609= 619465)

1000 meters = 1 km

so 619465 meters is 619.465 kilometers

Answer:

B They travel only through solids.

Explanation:

Seismic s-waves are also known as secondary or shear-waves. They are elastic waves that travels within a body.

Answer:

Alkali Metals

Explanation: