Pleaseeeeeeee Help ASAP!!

9. melting point

10. balloons float because they are filled with hydrogen, a gas which is less dense than air.

11. specific gravity

12. element

13. mixture

14. sodium and chlorine

15. cutting of paper

16. condensation

17. 1 and 3

18. heat energy is released

Answer:

See explanation

Explanation:

In Bohr's theory, electrons are found in specific regions in space called orbits. These orbits are also called energy levels. An electron may move from one energy level to another by absorbing or emitting energy.

In the wave mechanical model, electrons are not found in a particular region in space according to Heisenberg's uncertainty principle.

We rather define a certain region in space where there is a high probability of locating the electron. This region in space where there is a high probability of locating the electron is called an orbital.

Hence, in the Bohr's model of the atom,electrons can surely be found in orbits while in the wave mechanical model, the orbital is a probability function that describes a region in space where an electron may be found.

Answer:

A

Explanation:

becuase CaCI2 Is an inorganic compound

Answer:

according to me its c part which is correct

Answer:

B

Explanation:

. 2Ca(OH)2(aq) + Na2CO3(aq) 2CaCO3(s) + 2NaOH(aq)

A. Ca(OH)2(aq) + Na2CO3(aq) CaCO3(s) + 2NaOH(aq)

Answer:

The answer is A

Explanation:

hope it helps

[tex]\huge\fcolorbox{red}{pink}{Answer ♥}[/tex]

Life on Earth is based on carbon, likely because each carbon atom can form bonds with up to four other atoms simultaneously. This quality makes carbon well-suited to form the long chains of molecules that serve as the basis for life as we know it, such as proteins and DNA.

Hope it helps uh ✌️✌️✌️

Answer:

39.02 amu

Explanation:

The average atomic mass of an element can be calculated as follows :

[tex]X=\dfrac{9.67\times 38+78.68\times 39+11.34\times 40+0.31\times 41}{100}\\\\X=\dfrac{3902.29}{100}\\\\X=39.02\ amu[/tex]

So, the atomic mass of the element X is 39.02 amu.

1. Constellations are group of stars that form pattems in the night sky

2. Ursa Major, Cassiopeia, and Orion are some common constellations.

3. Stars are used to tell directions and time, predict weather, and to serve as birth sign.

Answer:

I'm pretty sure this is propanediol

Explanation:

I'm not sure how to explain it, but I believe this is the structure for propanediol. Please let me know if I misunderstood and don't hesitate to reach out with questions!

1,3-propan-diol is the chemical name the given structure: [tex]HOCH_2CH_2CH_2OH[/tex].

Chemical names are orderly systems for classifying and identifying various chemical compounds. They act as a benchmark for international scientific and research communication. For the development of many scientific domains, a standardised nomenclature system for chemicals must be created and adopted. Chemical names, which are made up of a combination of words and symbols, include detailed information on the make-up and structure of a certain substance. They frequently contain constituents, functional groups, and distinct modifiers that aid in describing the compound's varied attributes. 1,3-propan-diol is the chemical name the given structure: [tex]HOCH_2CH_2CH_2OH[/tex].

To know more about chemical name, here:

https://brainly.com/question/30633673

#SPJ6

Answer:

Wavelength = 0.049 m

Explanation:

Given that,

The frequency of a wave,[tex]f=6.1\times 10^9\ Hz[/tex]

We need to find the wavelength of the wave. We know that,

[tex]c=f\lambda\\\\\lambda=\dfrac{c}{f}\\\\\lambda=\dfrac{2.998 \times 10^8}{6.1\times 10^9}\\\\\lambda=0.049\ m[/tex]

So, the wavelength of the wave is 0.049 m.

Answer:

You should repent God is coming back soon

Answer:

The percentage efficiency of the electrical element is approximately 82.186%

Explanation:

The given parameters are;

The thermal energy provided by the stove element, [tex]H_{supplied}[/tex] = 3.34 × 10³ J

The amount thermal energy gained by the kettle, [tex]H_{absorbed}[/tex]  = 5.95 × 10² J

The percentage efficiency of the electrical element in heating the kettle of water, η%, is given as follows;

[tex]\eta \% = \dfrac{H_{supplied} - H_{absorbed} }{H_{supplied}} \times 100[/tex]

Therefore, we get;

[tex]\eta \% = \dfrac{3.34 \times 10^3 - 5.95 \times 10^2}{3.34 \times 10^3} \times 100 = \dfrac{549}{668} \times 100 \approx 82.186 \%[/tex]

The percentage efficiency of the electrical element, η% ≈ 82.186%.

Answer:

b

Explanation:

Molecular formula of Decanoic Acid is  C₁₀H₂₀O₂ therefore Option A is the right answer.

Decanoic Acid is a C10 , straight chain , saturated fatty acid . Its general formula is C₁₀H₂₀O₂ .

In the first option we can see a straight chain , saturated fatty acid and the molecular formula is also same as decanoic acid .

In second option the molecular formula is C₉H₁₈O₂ which is not same as Decanoic Acid.

Hence option A is the right answer.

To know more about Decanoic Acid;

https://brainly.com/question/8729762

#SPJ2

Answer:

12.01 grams per mole

Explanation:

theres no sample or example so if theres grams of Carbon, convert it to moles using 12.01g/mol

i know the answer is a theory

Answer:

Calculate the volume (in L) occupied by 3.40 g of NH3 at STP. (STP: 0 degree Celsius and 1 atmosphere of pressure).

Explanation:

To get the volume of ammonia gas at STP, calculate the number of moles of [tex]NH_3[/tex] in the given amount.

Number of moles of [tex]NH_3[/tex] gas is:

[tex]number of moles of NH_3 gas&=\frac{given mass of the gas}{its molecular mass} \\ &=\frac{3.40g}{17.0g/mol} \\&=0.2 mol.[/tex]

Since,

1 mol of any gas at STP occupies ------- 22.4 L of volume.

then,

0.2 mol of [tex]NH_3[/tex] occupies how much volume?

[tex]=>0.2 mol x \frac{22.4 L}{ 1.0 mol} \\=4.48 L[/tex]

Hence, the volume occupied by 3.40 g of ammonia at STP is --- 4.48 L.

Answer: Among the listed substances [tex]XeCl_{4}[/tex] is the molecular compound.

Explanation:

A chemical compound formed by the chemical combination of two or more non-metals is called a molecular compound or covalent compound.

For example, Xe and Cl are non-metals. The compound formed by them is [tex]XeCl_{4}[/tex] which is a molecular compound.

A molecular compound is formed by sharing of atoms between the combining atoms.

Whereas NaF, [tex]MnCl_{2}[/tex] and CaO are all ionic compounds as they are formed by chemical combination of a metal and a non-metal.

Thus, we can conclude that among the listed substances [tex]XeCl_{4}[/tex] is the molecular compound.

Answer:

0.067M H3PO4

Explanation:

H3PO4 reacts with NaOH as follows:

H3PO4 + 3NaOH → 3H2O + Na3PO4

Where 1 mole of H3PO4 reacts with 3 moles of NaOH

To solve trhis question we need to find the moles of NaOH required. With the chemical equation we can find the moles of H3PO4 and its concentration as follows:

Moles NaOH:

50.0mL = 0.0500L * (0.20moles /L) = 0.0100 moles NaOH

Moles H3PO4:

0.0100 moles NaOH * (1mol H3PO4 / 3mol NaOH) = 0.00333 moles H3PO4

Concentration:

0.00333 moles H3PO4 / 0.0500L = 0.067M H3PO4

Explanation:We have momemtum = mass X velocity

    p = mv

    OR, p/m = v

    v = (125kg m/s)25kg

    v = 125/25 m/s

       v = 5 m/s

Explanation:

hope it helps thanks ❤

brainliest please

Answer:

Explanation:

human obtains energy by eating food. as food is digested n broken down in our digestive system, energy is released to our body.

Answer:

C:Radiation

Explanation:

Pluto

Answer:

i hope this help

Explanation:

Radiation is a method of heat transfer that does not rely upon any contact between the heat source and the heated object as is the case with conduction and convection. Heat can be transmitted through empty space by thermal radiation often called infrared radiation. This is a type electromagnetic radiation.

Answer:

The combination of ions most likely to produce a precipitate is a group of answer choices:

lead nitrate soluble in water

Mg2+ and C2H3O2-.

Fe3+ and OH-.

Li+ and PO43-.

Pb2+ and NO3-.

NH4+ and SO42-.

Explanation:

Among the given options,

magnesium acetate, lithium phosphate, lead nitrate, ammonium sulfate are soluble in water.

The only one which is insoluble in water is [tex]Fe^3+[/tex] and [tex]OH^-[/tex] combination.

[tex]Fe(OH)_3[/tex] is insoluble in water. It forms a precipitate.

Answer:

For 1: 6.68 g of nitrogen dioxide will contain [tex]8.73\times 10^{22}[/tex] number of molecules

For 2: The given amount of nitrogen dioxide molecules has a mass of 41.31 g.

Explanation:

According to the mole concept:

1 mole of a compound contains [tex]6.022\times 10^{23}[/tex] number of molecules

The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)

We are given:

Mass of nitrogen dioxide = 6.68 g

Molar mass of nitrogen dioxide = 46 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of nitrogen dioxide}=\frac{6.68g}{46g/mol}=0.145mol[/tex]

Using above concept:

If 1 mole of a compound contains [tex]6.022\times 10^{23}[/tex] number of molecules

So, 0.145 moles of nitrogen dioxide will contain = [tex](0.145\times 6.022\times 10^{23})=8.73\times 10^{22}[/tex] number of molecules

Hence, 6.68 g of nitrogen dioxide will contain [tex]8.73\times 10^{22}[/tex] number of molecules

We are given:

Molecules of nitrogen dioxide = [tex]5.41\times 10^{22}[/tex] molecules

Using the above concept:

If [tex]6.022\times 10^{23}[/tex] number of molecules are present in 1 mole of a compound

So, [tex]5.41\times 10^{22}[/tex] number of molecules will be present in = [tex]\frac{1mol}{6.022\times 10^{23}}\times 5.41\times 10^{22}=0.898[/tex] moles of nitrogen dioxide

We know, molar mass of nitrogen dioxide = 46 g/mol

Using equation 1:

[tex]0.898mol=\frac{\text{Mass of nitrogen dioxide}}{46g/mol}\\\\\text{Mass of nitrogen dioxide}=0.898mol\times 46g/mol=41.31g[/tex]

Hence, the given amount of nitrogen dioxide molecules has a mass of 41.31 g.

Answer : Metal containers are not used for storing acid because most of the time acid reacts with almost every metal and produces salts or oxides which alters the acid characteristics making it useless .......