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Answer:

7g/cm³

Explanation:

Given parameters:

Mass of the mineral  = 21g

Volume  = 3cm³

Unknown:

Density of the mineral  = ?

Solution:

Density of a substance is the mass per unit volume of the substance.

 Density  = [tex]\frac{mass}{volume}[/tex]  

  Now insert the given parameters and solve;

  Density  = [tex]\frac{21}{3}[/tex]   = 7g/cm³

The mineral with a density of 7g/cm³ is Galena, an ore of lead.

Answer:

it contains O3, therefore making it an oxide

Answer:

iron (11) oxide

Explanation:

Percent yield of a reaction is the ratio of actual yield to the theoretical yield multiplied by 100. The percent yield of the reaction with the theoretical yield 34.6 g and actual yield of 25.2 g is 72.8%.

Percent yield is used compare the actual yield and theoretical yield of a reaction. It is the ratio of actual yield to the theoretical yield multiplied by 100.

Theoretical yield of a reaction is determined from the balanced chemical equation of the reaction. The actual yield or experimental value must vary from the stoichiometric expectation.

Given the theoretical yield = 34.6 g

actual yield = 25.2 g

percent yield  = actual yield/ theoretical yield × 100

= 25.2 g/ 34.6 g × 100 = 72.8 %

Therefore, the percent yield of the reaction is 72.8 %.

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Answer:

The answer is "23765.4"

Explanation:

Motor weight average number [tex](\bar{M_n}) = 1000000 \frac{g}{mol}[/tex]

Poly condensation degree dependent on the average number of molecular weights is as follows:

[tex]DP_n = \frac{\text{Mol.Wt Number Medium}}{\text{Monomer Unit Mol.Wt}}[/tex]

All monomer module, in this case, is propylene  

Sunrise. Unit Wt = Mol. Propylene weight

                           [tex]= \ Mol. \ Wt \ of \ C_3H_6\\\\= 3 \times 12.01 +6 \times 1.008 \ \ \frac{g}{mol}\\\\= 42.078 \frac{g}{mol}\\\\[/tex]

[tex]DP_n = \frac{1000000}{42.078}\\\\[/tex]

    [tex]=23765.4[/tex]

Answer:

A Cellulose not digested by humans.

b. the storage form of carbohydrates in plants is starch

C amylose contains 1-4 glycosidic bond

D Glycogen and starch are highly branched polysaccharides.

Explanation:

The name of one or more polysaccharides that matches each of the following descriptions are given as: a. not digestible by humans- cellulose, b. the storage form of carbohydrates in plants-starch, c. contains only oc (1-4)-glycosidic bonds-amylose, d. the most highly branched polysaccharide-glycogen.

Monosaccharides—repeated sugar units—are joined by glycosidic linkages to form polysaccharides, which are large, complex carbohydrates. They are polymers consisting of hundreds of monosaccharide molecules or even thousands of them.

a. Humans cannot digest the carbohydrate known as cellulose. It is a part of the structure of plant cell walls.

b. The plant stores carbohydrates in the form of starch. It functions as a store of energy and is made up of the molecules amylose and amylopectin.

c. A polysaccharide called amylose only has linkages that are (1-4)-glycosidic. It consists of glucose units joined together by (1-4)-glycosidic linkages, and is a linear polymer.

d. The polysaccharide that has the most branches is glycogen. In particular, the liver and muscles, it is the most prevalent form of carbohydrate storage in both animals and people.

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The result of the calculation to the proper number of significant figures will be 31.6.

There are certain rules guiding significant figures in mathematical operations.

Following the first rule:

1.4 + 15 + 7.15 + 8.003 = 31.553

The participating number with the lowest significant digit after the decimal is 1.4 with just one significant digit. Thus, the final answer would be 31.6.

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The ionization energy increases as the ration of protons to electrons increases.

On the periodic table, as we move from left to right through a period, the initial ionization energy rises. This is due to the outermost electron becoming more closely bound to the nucleus as the nuclear charge increases.

Ionization energy - the energy needed to remove an electron from a gaseous atom, is the one that best exemplifies periodic behavior.

The energy needed to remove each additional electron from an atom grows gradually, with the removal of an electron from a filled inner shell causing a significant increase.

A stable atom becomes electrically imperfect or imbalanced if we remove one of its electrons. In other words, the nucleus's protons (positive charges) outnumber its electrons (negative charges). It is a positive ion because the atom has a plus-one charge after losing an electron.

Therefore on removing the second electron more ionization energy will be required than first. So option D is correct.

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Answer:

a) 2.01 g

Explanation:

First we convert 0.0302 mol AgNO₃ to Na₂CO₃ moles, in order to calculate how many Na₂CO₃ moles reacted:

So the remaining Na₂CO₃ moles are:

Finally we convert Na₂CO₃ moles into grams, using its molar mass:

The closest answer is option a).

The molar mass of gas = 206.36 g/mol

In general, the gas equation can be written

[tex]\large{\boxed{\bold{PV=nRT}}}[/tex]

where

P = pressure, atm

V = volume, liter

n = number of moles

R = gas constant = 0.082 l.atm / mol K

T = temperature, Kelvin

mass (m)= 2.89 g

volume(V) = 346 ml = 0.346 L

T = 28.3 C + 273 = 301.3 K

P = 760 mmHg=1 atm

The molar mass (M) :

[tex]\tt PV=\dfrac{m}{M}RT\\\\M=\dfrac{mRT}{PV}\\\\M=\dfrac{2.89\times 0.082\times 301.3}{1\times 0.346}\\\\M=206.36~g/mol[/tex]

Answer:

The picture represents oxygen.

Explanation:

There are two notable ways you can figure this out:

1) Since there are eight protons, you can automatically know that you are looking for an element with an atomic number of 8. This is because the atomic number is the number of protons in an atom.

2) You can also note the number of electrons on the outer shell. These are called valence electrons. You can then see that the element has 6 valence electrons. Beginning with Lithium on the periodic table and count by ones going from left to right in period 2 of the periodic table until you get to 6. What element is that? It is indeed oxygen.

Answer:

Oxygen

Explanation:

Neons contain 8 protons and 10 ELECTRONS

Boron contains 5 protons an 5 electrons

calcium contains 20 electrons an 0 protons

Answer:

D atom

Explanation:

The smallest particle of a substance that retains the chemical and physical properties of the substance and is composed of two or more atoms

Answer:

an insulator is right answer

Explanation:

i hope it is helpful for you

Answer:

Barium carbonate powder is stirred add pulp in the entry, the vitriol that the adds solubility then reaction that makes the transition is filtered and is obtained the barium sulfate filter cake and liquid after the transition.

Answer:

☑ Friction between an object and chair

☐ The force between two magnets

☐ The force between two charged particles

☐ The gravitational pull of a planet

Answer:

Oceanic crust is not only thinner and denser than continental crust, and it is also much younger than it and has a different chemical composition. When magma from the mantle of the earth finds a way up, it comes into contact with water that cools it down quickly

Answer:

nuclear energy

Explanation:

heat and light is due to release of energy due to nuclear fusion in the sun

Answer:

Chemical energy

Explanation:

Answer:

d 2,4,3

Explanation:

2 Al2O3 ----> 4 Al + 3 O2

To solve such this we must know the concept of redox reaction. Therefore, the correct option is option D. the balanced decomposition chemical reaction can be given as

2 Al[tex]_2[/tex]O[tex]_3[/tex] [tex]\rightarrow[/tex] 4 Al + 3 O[tex]_2[/tex]

Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.

Decomposition reaction is a reaction which one reactant breaks down into two or more products in presence of energy in the form of heat or electricity. The balanced decomposition chemical reaction can be given as

2 Al[tex]_2[/tex]O[tex]_3[/tex] [tex]\rightarrow[/tex] 4 Al + 3 O[tex]_2[/tex]

Therefore, the correct option is option D. the balanced decomposition chemical reaction can be given as

2 Al[tex]_2[/tex]O[tex]_3[/tex] [tex]\rightarrow[/tex] 4 Al + 3 O[tex]_2[/tex]

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427 g Mo

Chemistry

Atomic Structure

Math

Pre-Algebra

Order of Operations: BPEMDAS

Step 1: Define

2.68E24 atoms Mo or 2.68 × 10²⁴ atoms Mo

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of Mo - 95.94 g/mol

Step 3: Convert

[tex]2.68 \cdot 10^{24} \ atoms \ Mo(\frac{1 \ mol \ Mo}{6.022 \cdot 10^{23} \ atoms \ Mo} )(\frac{95.94 \ g \ Mo}{1 \ mol \ Mo} )[/tex] = 426.966 g Mo

Step 4: Check

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

426.966 g Mo ≈ 427 g Mo

Answer:

well i think coffe is an example cause it goes from hot to cold

Answer:

bent

Explanation:

The chlorite ion has been pictured in the image attached with its two main resonance contributors.

The ion has four regions of electron density as shown. On the basis of the VSEPR theory, we expect a tetrahedral geometry.

However, the ion is bent due to the effect of the lone pairs on chlorine which is the central atom in the ion. This distorts the bond angle of the ion hence the ion has a bent molecular geometry.

Answer:

29.7g of NO are present

Explanation:

With volume, absolute temperature and pressure we can determine moles of ammonia and oxygen that reacts. With these moles we can determine limiting reactant and moles (And mass) of nitrogen monoxide produced as follows:

Moles Ammonia:

PV = nRT

PV/RT = n

1.26atm*33.7L / 0.082atmL/molK*296.3K = 1.748 moles ammonia

Moles Oxygem:

PV = nRT

PV/RT = n

1.26atm*41.3L / 0.082atmL/molK*296.3K = 2.142 moles oxygen

Based on the chemical reaction, 1 mole of NH3 reacts per mole of O2 producing 1 mole of NO.

Thus, limiting reactant is ammonia and moles of NO produced are = Moles of ammonia added = 1.748mol NH3

Mass Ammonia:

1.748mol NH3 * (17g/mol) =

Answer:

ch2coo3 is the reaction of mechanism

Answer:

6CO2 + 6H2O → C6H12O6 + 6O2 is a balanced equation

Explanation:

Carbon, Oxygen, Hydrogen

Reactants are carbon dioxide and water, products are glucose and oxygen

Dynamic Equilibrium I have no idea about (soz)

I believe this might be endothermic

Answer:

4.44 x 10^14 Hz

Explanation:

The frequency of light is 0.00148 Hz. This can be determined y using the value of wavelength.

It is defined as the reciprocal of the wavelength.

Frequency =  1 /  wavelength

Given:

Wavelength = 675 nm

To find:

Frequency=?

On subsituting the values:

f= 1/ 675 nm

f=0.00148 Hz

Thus, the frequency of light is 0.00148 Hz.

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The  the precipitate : Al(OH)₃(s)

The spectator ions : 3Cl⁻ and 3K⁺

Reaction

AlCl₃ + 3KOH → Al(OH)₃ + 3KCl

From solubility rules :

Compounds of OH− are insoluble except Compounds of Li +, Na +, K +, Rb +, Cs +, NH₄⁺ , Sr²⁺, and Ba²⁺

Compounds of Cl−, Br−, I− are soluble except Ag⁺, Hg₂²⁺, Pb²⁺

So the  the precipitate : Al(OH)₃(s)

net ionic reaction

AlCl₃ + 3KOH → Al(OH)₃ + 3KCl

Al³⁻+3Cl⁻+3K⁺+3OH⁻⇒Al(OH)₃(s)+3K⁺+3Cl⁻

Remove the spectator : 3Cl⁻ and 3K⁺

Al³⁻(aq)+3OH⁻(aq)⇒Al(OH)₃(s)

Answer:

Carbon Dioxide

Explanation:

Because plants take in Carbon Dioxide, then let out Oxygen

The mass of H atoms in 187g of zinc hydroxide Zn(OH)₂ is 3.76 gm

Given,

The molar mass of zinc hydroxide = 99.43 g/mol

We have to find the mass of the hydrogen atoms in 187 gm of zinc hydroxide.

Mass of H in 99.43 g of Zn(OH)₂ = 2 gm

Mass of H in 1 g of Zn(OH)₂ = 2 / 99.43

Mass of H in 187 g of Zn(OH)₂ = 0.02 × 187 gm

Or, the mass of H in 187 g of Zn(OH)₂ is 3.76 gm

The molecular mass of any substance tells us the sum of atoms present in the compound. The number of moles can be calculated by the given mass to the molecular mass.

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Answer:

ZnCl2

H2

Explanation:

The products of the given reaction is:

      ZnCl₂  and H₂

The two species are the products of the chemical combination

Answer:

II

Explanation:

We must have a good idea of the fact that there are two mechanisms that come into play when we are discussing about the addition of hydrogen halides to alkenes. The first is the ionic mechanism and the second is the radical mechanism.

The ionic mechanism is accounted for by the Markovnikov rule while the radical mechanism occurs in the presence of peroxides and is generally referred to as anti Markovnikov  addition.

The intermediate in anti Markovnikov  addition involves the most stable radical, in this case, it is a tertiary radical as shown in the images attached. The most stable radical is II hence it leads to the major product shown in the other image.

Answer:

need what?? I would love to help though!

Answer:

Explanation:

IN order for us to help you, we would like to know the question.