Which set of the below elements are in the same period.

1. Li, Be, C, O

2. H, Li, Be

3. F, CI, Br, I

4. H, He, Li, Be

Answer:

18.3%

Explanation:

Add the numbers together, and then take the number of grams of the substance, in this case copper, not coppper lol. divide the .45 by 2.45 to get 18.3

Answer:

A. Solid aluminum oxide and solid iron

Explanation:

The reaction equation is given as:

    2Al  +   Fe₂O₃  →   Al₂O₃   + 2Fe

The species on the left hand side are the reactants

Those on the right hand side of the expression are the products.

The products are:

Al₂O₃   and Fe

 These are solid aluminum oxide and solid iron

Tubular organism with tentacles surrounding its mouth; a cnidarian

Hydra

SORRY I DON'T KNOW CORRECT BUT

I THOUGHT THATH THIS IS A CATEPILLAR

PLEASE THANKS THIS ANSWER

Answer:

1280L

Explanation:

Given parameters:

Initial pressure  = 0.727atm

Temperature  = 26.9°C

Initial volume  = 726mL  = 0.726L

New pressure  = 0.412atm

Unknown:

New volume of the gas sample  = ?

Solution:

To solve this problem, we apply boyles law;

            P1V1  = P2V2

P and V are pressure and temperature

1 and 2 are initial and new state

             0.727 x 0.726  = 0.412 x V2

                   V2  = 1.28mL  = 1280L

Moles of Carbon dioxide : n = 4.037 x 10⁻³

Given

2.43 x 10²¹ molecules of Carbon dioxide

Required

Moles

Solution

1 mol = 6.02 x `10²³ particles(molcules, atoms, ions)

Can be formulated :

N = n x No

n = moles

No = Avogadro's number 6.02 x `10²³

moles of Carbondioxide :

n = N/No

n = 2.43 x 10²¹ / 6.02 x `10²³

n = 4.037 x 10⁻³

Answer:

3 atoms of O

8.57g

Explanation:

The problem here is to find the mass of oxygen in the compound and the number of atoms of oxygen.

 The formula of the compound is:

 NaHCO₃;

   Here we have:

      1 atom of Na

     1 atom of H

     1 atom of C

     3 atoms of O

So there are 3 atoms of O

To find the mass of oxygen , we use the molar mass of oxygen;

     Molar mass of oxygen  = 16g/mol

 Mass of oxygen  = [tex]\frac{3(16)}{84.01}[/tex]  x 15  = 8.57g

Answer:

I believe the answer is A. molecules are larger than atoms so they should be visible and atoms and molecules are indeed different

To see the number of atoms of an element in a given molecule we need to multiply stoichiometry to the number that is written on the foot of the element that is stoichiometry. Therefore, the correct option is option A.

Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.

In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. So overall the charge of nucleus is due to only proton, not by neutron.  Most atoms are bonded together to make a molecule. Molecules combine to form compounds.

Therefore, the correct option is option A.

To know more about atom, here:

https://brainly.com/question/13518322

#SPJ2

Answer:

D . A substance with a pH of 8

Explanation:

pH stands for "Potential for Hydrogen." This is an indicator of a solution's acidity or alkalinity. It is also used to tell which chemicals are great for cleaning.

pH 7 and pH 8 are both considered "neutral pH," thus, solutions with these pH are often used as dishwashing detergents because they do not destroy the surfaces of objects. However, pH 8 is said to be more alkaline in nature. This allows it to destroy the residues, such as fats and oils, in pots and pans. It is the pH of baking soda.

Answer:

All except a diamond

Explanation:

The helium in the balloon has mass it fills the space its in.

The neon-filled tube has mass because it takes up space.

Water in a glass has mass because the water is taking up space.

A diamond does not because it does not take up space.

Answer:

Lithium sulphate (Li₂SO₄) and water (H₂O

Explanation:

H₂SO₄ + 2LiOH —> Li₂SO₄ + 2H₂O

The equation represented above indicates a neutralization reaction.

A neutralization reaction is a reaction involving acid and base which result in the production of salt and water.

In the equation above,

Reactant:

H₂SO₄ (acid)

LiOH (base)

Product:

Li₂SO₄ (salt)

H₂O (water)

Thus, lithium sulphate (Li₂SO₄) and water (H₂O) are the products of the reaction

Answer:

B: It is extremely reactive

Explanation:

Potassium metal is also soft and white with a silvery lustre, has a low melting point, and is a good conductor of heat and electricity.

Answer: Properties, occurrence, and uses. Potassium metal is soft and white with a silvery lustre, has a low melting point, and is a good conductor of heat and electricity. Potassium imparts a lavender colour to a flame, and its vapour is green.

Explanation: hope it helps

Answer:

bond

Explanation:

It is a polar bond because it is when two atoms bond

Answer:

E) Plants take carbon from the atmosphere

Explanation:

Plants are a vital part in keeping the air clean. They take in CO2, H2O, and sunlight to start processing photosynthesis. The carbon taken in by the plant still remains with it after it dies, thus, fossil fuels.  

Answer:

e is correct

Explanation:

Answer:

VALENCE ELECTRONS are involved in the bonding of atoms

Explanation:

Hope that helps

Answer:

B. Halogen

Explanation:

Halogens are the family of chemical elements found in the group VIIA of the periodic table which means they possess seven (7) outer electrons. Some examples of halogens are Fluorine (F), Iodine (I), Bromine (Br), and Chlorine (Cl).

A halogen, or an element located in group 7A, will form a salt when reacted with a metal atom.

For example, when Chlorine reacts with Sodium it would form a salt known as Sodium Chloride.

Na + Cl ----> NaCl

Answer:

Each sample has the same number of molecules.

Explanation:

Just took the quiz on edge 2021

Taking into account the definition of Avogadro's number, each sample has the same number of molecules.

Avogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023×10²³ particles per mole.

Avogadro's number applies to any substance.

Avogadro's number applies to any substance. This means that the number of molecules in 1 mol of oxygen is equal to the number of molecules in 1 mol of nitrogen.

Finally, the correct answer is the third option: each sample has the same number of molecules.

Learn more about Avogadro's Number:

brainly.com/question/1445383

brainly.com/question/1528951

Answer:

Excited State Configuration: 1s^2 2s^2 2p^4 3s^1 are sperated by 13.00 eV.

Answer:  [tex]6.047\times 10^{23}[/tex] atoms in 1.004 mol of arsenic

Explanation:

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.

To calculate the atoms, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given atoms}}{\text {avogadro's number}}[/tex]

[tex]1.004=\frac{x}{6.023\times 10^{23}}[/tex]

[tex]x=1.004\times 6.023\times 10^{23}=6.047\times 10^{23}[/tex]

Thus there are [tex]6.047\times 10^{23}[/tex] atoms in 1.004 mol of arsenic

Answer:

6.) mixture

8.) compound

Answer:

C3H8

Propane/Formula

Explanation:

hope this helps

Answer:

diet soda has artificial sugar and regular soda has insane amounts of sugar

Answer:

Disagree with the suggestion based on the hygroscopic nature of anhydrous magnesium sulfate

Explanation:

Magnesium sulfate in the anhydrous form is a drying agent. A drying agent salts of inorganic compounds that has the capability of absorbing water to become hydrated, when placed in the presence of a wet surface or moist air

Anhydrous magnesium sulfate is therefore hygroscopic such that it absorbs water from the atmosphere and becomes hydrated and increases in size as its volume is increased according to the following chemical equation

MgSO₄(s) + 7H₂O(l) → MgSO₄·7H₂O(s)

The molar mass of anhydrous magnesium sulfate = 120.366 g/mol

The molar mass of the heptahydrate = 246.47 g/mol

Therefore, the mass of the magnesium sulfate doubles when it forms the heptahydrate, and the magnesium sulfate grows bigger.

Answer:118

Explanation: it’s right

Answer:

118 elements

Hope that helps

166 g HCl

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Stoichiometry

Step 1: Define

[RxN - Unbalanced] Mg (s) + HCl (aq) → MgCl₂ (aq) + H₂ (g)

[RxN - Balanced] Mg (s) + 2HCl (aq) → MgCl₂ (aq) + H₂ (g)

[Given] 2.28 mol Mg (s)

Step 2: Identify Conversions

[RxN] 1 mol Mg = 2 mol HCl

Molar Mass of H - 1.01 g/mol

Molar Mass of Cl - 35.45 g/mol

Molar Mass of HCl - 1.01 + 35.45 = 36.46 g/mol

Step 3: Stoichiometry

Step 4: Check

Follow sig fig rules and round. We are given 3 sig figs.

166.258 g HCl ≈ 166 g HCl