1.Explain why the reactivity of group 7 decreases as you move down the group. Try to use the sentence starters here: When group 7 elements react, their atoms….

As you move down the group, the outer shells get…

Therefore the force of attraction between the shells and the nucleus is….

This makes attracting an extra electron…​

Answer:

False

Explanation:

Not all molecules are compounds, since some molecules, such as oxygen gas (above image of molecule of-O2) or ozone (O3), consist only of one element or type of atom. Water is also a molecule because it is made from atoms that have been chemically combined.

Answer:

pH = 1.6

Explanation:

pH + pOH = 14

=> pH + 12.4 = 14

∴ pH = 1.6

pls mark it as the brainliest

Answer: 27 electrons

copper has 29 protons in its nucleus. atoms can only lose or gain electrons. so because copper has 29 protons and will always have 29 protons, and the Cu2+ ion has a positive charge, there are more protons than electrons.

that means there should be 2 less electrons than protons. that leaves us with 29 protons and 27 electrons.

hope this helps :)

Answer:

because no chemical change is happening

Explanation:

Answer:

375.8 × 10²³ molecules

Explanation:

Given data:

Number of molecules of acetylene = ?

Volume of cylinder = 1400 L

Temperature = standard = 273.15 K

Pressure = standard = 1 atm

Solution:

The given problem will be solve by using general gas equation,

PV = nRT

P= Pressure

V = volume

n = number of moles

R = general gas constant = 0.0821 atm.L/ mol.K  

T = temperature in kelvin

PV = nRT

1 atm × 1400 L = n ×  0.0821 atm.L/ mol.K    × 273.15 K

1400 L.atm = n × 22.43  atm.L/ mol

n = 1400 L.atm / 22.43  atm.L/ mol

n = 62.4 mol

1 mole contain 6.022 × 10²³ molecules

62.4 mol × 6.022 × 10²³ molecules / 1 mol

375.8 × 10²³ molecules

Answer:

double covalent bonds in carbon di oxide

Carbon dioxide is a covalent compound formed by carbon and oxygen. There are two covalent double bonds between carbon and each oxygens. Thus option d is correct.

Covalent bond is a type of bond formed by the sharing of electrons between two atoms. Whereas, ionic bond is formed by lose or gain of electrons. Covalent bond is weaker than the ionic bond.

Carbon contains 4 electrons in its valence shell. Thus it needs 4 more electrons to attain stability. Oxygen contains two electrons in its valence shell and thus it needs 2 more electrons to become stable

A double bond is formed when two electrons are shared between two atoms. Thus, oxygen shares its two electron with carbon. And the second oxygen also shares its two electrons. Thus carbon attain 4 more electron and become stable.

Carbon shares its two electron with one oxygen and other two electron with the second oxygen thus, make each oxygen attains octet and become stable. Thus, the two straight lines between carbon and oxygen is double covalent bonds.

To find more about covalent bonds, refer the link below:

https://brainly.com/question/19382448

#SPJ2

Answer:

The correct statement is;

(B) Only II

Explanation:

I) The atomic mass unit or amu which is also known as daltons which is defined as 1/12 × the mass of a carbon-12 atom, which is therefore, 1.660538921 × ⁻²⁴ grams

Therefore, the mass of 1 atom of carbon-12 = 12 amu

II) The mass of one mole of oxygen-16 is 16 grams while the mass of one mole of carbon-12 is 12 grams

The mass of 4 atoms of carbon 12 = 4 × 12 amu = 48 amu

The mass of 1 atom of oxygen-16 = 15.99491461956 amu

Therefore, the mass of 3 atoms of oxygen-16 = 3 × 15.99491461956 = 47.9847438587 amu ≈ 48 amu

Therefore only II is correct.

Answer:

c is your answer

Explanation:

So, 53.49 g (M) of NH4Cl N H 4 C l contains 14.01 g (m) of N . So, the mass percent of nitrogen in NH4Cl N H 4 C l is 26.19%.

Answer: The density of chloroform is 1.47 g/mL

Explanation : Given,

Volume = 40.5 mL

Mass of cylinder = 85.16 g

Mass of cylinder and liquid = 145.10 g

First we have to calculate the mass of liquid (chloroform).

Mass of liquid = Mass of cylinder and liquid - Mass of cylinder

Mass of liquid = 145.10 g - 85.6 g

Mass of liquid = 59.5 g

Now we have to calculate the density of liquid (chloroform).

Formula used:

[tex]Density=\frac{Mass}{Volume}[/tex]

Now putting g all the given values in this formula, we get:

[tex]Density=\frac{59.5g}{40.5mL}[/tex]

[tex]Density=1.47g/mL[/tex]

Therefore, the density of chloroform is 1.47 g/mL

Answer:

3 chlorine atoms are needed because each chlorine atom accepts one of  Aluminum three valence electrons to obtain a full octet and makes chlorine a  negatively charged anion

Explanation:

How many chlorine atoms are needed when making Aluminium Chloride?

The formular for aluminium chloride is given as; AlCl3

In the compound, Aluminium has a valency of +3 and the three chlorine atoms each have a valency of +1 to make the compound a neutral compound.

That meas we can represent AlCl3 as Al³⁺ and 3Cl⁻

The correct statement is;

3 chlorine atoms are needed because each chlorine atom accepts one of  Aluminum three valence electrons to obtain a full octet and makes chlorine a  negatively charged anion

Answer: sorry I’m late but it is 11 electrons

Explanation:

Answer:

C) ionic compounds

Explanation:

Only ionic compounds takes place in a chemical double displacement reaction.

The reaction involves an actual exchange of partners to form a new compounds.

These compounds involved are ionic compounds.

Answer:

well, u can figure that out by multiply that amount by Avocado's number, which is 6.022x10 to the power of 23

Answer:

Water

Explanation:

hope that helps:)

Answer:

427.5g

Explanation:

Given parameters:

Number of moles  = 4.5moles

Unknown:

Mass of MgCl₂  = ?

Solution:

To solve this problem;

     Mass  = number of moles x molar mass

Molar mass of MgCl₂  = 24 + 2(35.5) = 95g/mol

  Mass  = 4.5 x 95  = 427.5g

Answer:

Explanation:

Outer skin cells form flattened stacks that protect the body from the environment. Muscle cells are slender fibers that bundle together for muscle contraction. The cells of multicellular organisms may also look different according to the organelles needed inside of the cell.

Answer:

theres no picture

Explanation:

Answer:

I FINNALY GOT MY HANDS ON THE AWNSER, dont

copy word for word though Explanation:

Simulation of a reaction is a chemical reaction modeling or demonstration tool, using various software to better understand the molecular structure and the physical and chemical properties of the molecule. Here the actual reaction is N2 + 3H2 -----> 2NH3. In the simulation reactions, the nitrogen and hydrogen molecules in the actual reaction are described by different colored circles or dots and the bonds are produced using a single, double or triple line that touches each molecule and gives an appearance like the reactants and the products' ball and stick model. Example: Molecule of nitrogen as o---triple line---o. A molecule of hydrogen as O———O. Chemical symbols such as N and H are expressed in Actual Chemical Reaction, N2 and H2 and the bonds are represented by single, double or triple lines that do not impact the atoms in the molecule as follows: Nitrogen Molecule: N -triple Bond- N. Hydrogen Molecule: H - H.

Answer:

it is a physics questions not chemistry

Explanation:

speed=distance/time

so distance =speed * time

=120*4

=480 km

Answer:

solid and liquid state respectively

Answer:

A - solid, liquid

Explanation:

ur welcome

Answer:b

Explanation:

Answer:

Half of Earth’s oceans are not owned by any particular country.

Explanation:

Reducing oil pollution requires an international effort because ocean waters do not have boundaries and there are certain portion of the ocean that are not owned by any nation.

International collaborations are sought to combat any issue of oil spillage due to global undertone to it.

Answer:

False

Explanation:

Please mark brainlliest if you want and mark 5 stars please. Thank you and have a good day.

Answer:

The correct answer is  - 32 cells.

Explanation:

In the meiosis type of cell cycle or cell division, a single parent cell divides into four daughter cells, unlike mitosis. Meiosis takes place in the reproductive or sex cell and called reduction division.

As we know each cell divide into four daughter cells.

1  reproductive cell = 4 daughter cells

2 reproductive cell = 8 daughter cells

Now each daughter cell undergo meiosis than each cell will produce 4 cells so,

8 daughter cells will produce:

8 *4 = 32 cells.

Thus, the correct answer is  - 32 cells.

Answer:

I think it's B.

Answer:

logarithmic

Explanation:

Answer:

Mass = 21.58 g

Explanation:

Given data:

Mass of MgCl₂ = 35 g

Mass of Mg(OH)₂ produced = ?

Solution:

Chemical equation:

MgCl₂ + 2KOH    →     Mg(OH)₂ + 2KCl

Number of moles of MgCl₂:

Number of moles = mass/molar mass

Number of moles = 35 g/ 95.2 g/mol

Number of moles = 0.37 mol

now we will compare the moles of MgCl₂ and Mg(OH)₂

                MgCl₂         :        Mg(OH)₂

                   1               :            1

                 0.37           :        0.37

Mass of  Mg(OH)₂ :

Mass = number of moles × molar mass

Mass = 0.37 mol × 58.32 g/mol

Mass = 21.58 g

a. HI(g) ⇒ H₂9g) + I₂(g)

b. Al(s) + I₂(s)⇒AlI₃(s)

c. FeO(s)+O₂(g)⇒Fe₂O₃(s)

Given

word equations

Required

skeleton equations

Solution

The skeleton equation shows the chemical formula of the reaction between reactants and products, regardless of the actual amount of the reacting compound (unbalanced reaction)

The skeleton equations :

a. HI(g) ⇒ H₂9g) + I₂(g)

b. Al(s) + I₂(s)⇒AlI₃(s)

c. FeO(s)+O₂(g)⇒Fe₂O₃(s)

Answer:

A. Designing a device that is biologically compatible

Explanation: