1. Atoms have a positive charge.
True or false

Answer:

0.714 in scientific notation is 7.14 × 10-1.

Answer: m × 10n, where m is a number between 1 and 10 ( 1 ≤ |m| < 10 ) and the exponent n is a positive or negative integer.

Explanation:

1) Move the decimal 1 times to right in the number so that the resulting number, m = 7.14, is greater than or equal to 1 but less than 10

2) Since we moved the decimal to the right the exponent n is negative

n = -1

3) Write in the scientific notation form m × 10n

= 7.14 × 10-1

Therefore,

7.14 × 10-1 is the scientific notation form of 0.714 number and 7.14e-1 is the scientific e-notation form for 0.714

Answer:

The list is limited to 20 most important contributors or, if less, a number sufficient to account for 90% of the provenance. The listed Reaction acts as a link to the relevant references for the measurement. The Measured Quantity is normaly given in the original units; in cases where we have reinterpreted the original measurement, the listed value may differ from that given by the authors. The quoted uncertainty is the a priori uncertainty used as input when constructing the initial Thermochemical Network, and corresponds either to the value proposed by the original authors or to our estimate; if an additional multiplier is given in parentheses immediately after the prior uncertainty, it corresponds to the factor by which the prior uncertainty needed to be multiplied during the ATcT analysis in order to make that particular measurement consistent with the prevailing knowledge contained in the Thermochemical Network.

Explanation:

Answer:

3. B

4. B

5. C

6. A

7. D

8. C

Explanation:

3. A material or substance is said to be BRITTLE If it can be broken easily when there is an application of force e.g glass

4. A material that cannot conduct heat and electricity is called an INSULATOR. Among the given options, WOOD is a poor conductor of heat i.e. it cannot withstand hear. Iron, gold and copper are all metals, hence, very good conductors.

5. Matter which constitutes all substances tend to react with one another, however, when the observed trait or characteristic is called a CHEMICAL PROPERTY.

6. Physical property of matter can either be intensive or extensive. INTENSIVE PHYSICAL PROPERTY is that characteristic or trait of matter that does not depend on the amount. Example is temperature, density etc

7. PHYSICAL PROPERTY is the property of matter that can be observed or perceived with our senses easily without changing its chemical composition or nature. Example of physical property is melting.

8. Matter exists in three states; solid, gas and liquid. In the GASEOUS state of matter, particles are relatively far apart or scattered and practically independent of each other. This allows gas to be able to diffuse.

Explanation:

Given

Weight of Water (H2O) = 6.4 gms

To find

Number of moles of water = ?

Solution

we know that molar mass of H2O = 18 g

Now,

[tex]Number \: of \: moles =\frac{Given \: weight \: of \: substance}{molar \: mass \: of \: substance} [/tex]

Number of moles = 6.4/18 = 0.355~ 0.36 moles

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Answer:

Explanation:

h2o   =  18 gmol-1

             1mol =18 g

             18 g  =1mol

             6.4g =1/18*6.4

                      = 0.355

                      =0.36mol

(i) The volume of  1.00 M HCl neutralized by two of these ingestion tablets is 20.6 mL

(ii) The mass of salt formed in the neutralization reaction is 0.98 g

(iii) The number of magnesium ions present in that amount of salt is 6.19 × 10²¹ ions

(i) From the question, we are to calculate the volume of 1.00 M HCl neutralized two of the ingestion tablets

From the given balanced chemical equation

Mg(OH)₂(aq) + 2HCl(aq) ⟶ MgCl₂(aq) + 2H₂O(l)

This means,

1 mole of Mg(OH)₂ is neutralized by 2 moles of HCl to give 1 mole of MgCl₂

Now, we will determine the number of moles of Mg(OH)₂ present in two of the ingestion tablets

From the given information

Mass of Mg(OH)₂ in 1 ingestion tablet = 0.30 g

∴ Mass of Mg(OH)₂ in 2 ingestion tablets = 0.60 g

Using the formula,

[tex]Number\ of\ moles = \frac{Mass}{Molar\ mass}[/tex]

Molar mass of Mg(OH)₂ = 58.33 g/mol

Then,

Number of moles of Mg(OH)₂ in 2 ingestion tablets = [tex]\frac{0.60}{58.33}[/tex]

Number of moles of Mg(OH)₂ in 2 ingestion tablets = 0.0102863 mole

Now,

If 1 mole of Mg(OH)₂ is neutralized by 2 moles of HCl

Then,

0.0102863 mole of Mg(OH)₂ will be neutralized by 0.0205726 moles of HCl

∴ The number of moles of HCl that would neutralize 2 ingestion tablets is 0.0205726 mole

Now, for the volume of 1.00 M HCl neutralized by two ingestion tablets

Using the formula,

[tex]Volume = \frac{Number\ of\ moles}{Concentration}[/tex]

Volume = [tex]\frac{0.0205726}{1.00}[/tex]

Volume = 0.0205726 L

Volume = 20.5726 mL

Volume ≅ 20.6 mL

Hence, the volume of  1.00 M HCl neutralized by two of these ingestion tablets is 20.6 mL

(ii) For the mass of salt (MgCl₂) formed in the neutralization reaction

Since 1 mole of Mg(OH)₂ is neutralized by 2 moles of HCl to give 1 mole of MgCl₂

Then,

0.0102863 mole of Mg(OH)₂ will be neutralized by 0.0205726 moles of HCl  to give 0.0102863  mole of MgCl₂

∴ The number of moles of the salt (MgCl₂) formed is 0.0102863 mole

For the mass of the salt formed,

Using the formula,

Mass = Number of moles × Molar mass

Molar mass of MgCl₂ = 95.211 g/mol

∴ Mass = 0.0102863 × 95.211

Mass = 0.9793689 g

Mass ≅ 0.98 g

Hence, the mass of salt formed in the neutralization reaction is 0.98 g

(iii) For the number of magnesium ions present in that amount of salt,

1 mole of MgCl₂ contains 1 mole of magnesium ions

Then,

0.0102863 mole of MgCl₂ will contain 0.0102863 mole of magnesium ions

From the formula,

Number of ions = Number of moles × Avogadro's constant

Avogadro's constant = 6.022 × 10²³ mol⁻¹

∴ Number of magnesium ions present = 0.0102863 × 6.022 × 10²³

Number of magnesium ions present = 0.061944 × 10²³

Number of magnesium ions present = 6.1944 × 10²¹

Number of magnesium ions present ≅ 6.19 × 10²¹ ions

Hence, the number of magnesium ions present in that amount of salt is 6.19 × 10²¹ ions

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bro is that genius cast that's an easy line

I can easily draw that

Answer:

.75 meter north

Explanation:

v = d/t

v = 15/20

v = .75

Answer:

C. 12.5 m/s

Explanation:

h = h(0) - gt²/2

0 m = 8 m - 9.8 m/s²*t²/2

- 8 m = - 9.8 m/s²*t²/2

16 m = 9.8 m/s² * t²

t² = 16/9.8 s²

t = √(16/9.8) s

v = v(0) + gt

v = 0 +gt

v = 9.8 m/s² * √(16/9.8) s ≈ 12.5 m/s

Answer:

2.33 g H20

Explanation:

12.1 grams of water are produced when 5.38g of O₂ is reacted.

The mole is an amount unit similar to familiar units like pair, dozen, gross, etc. It provides a specific measure of the number of atoms or molecules in a bulk sample of matter.

A mole is defined as the amount of substance containing the same number of atoms, molecules, ions, etc. as the number of atoms in a sample of pure 12C weighing exactly 12 g.

Given,

Mass of oxygen = 5.38g

Moles = mass / molar mass

Moles of oxygen = 5.38 / 16

                             = 0.34 moles

From the reaction,                      2H₂ + O₂ = 2 H₂O

1 mole of oxygen gives 2 moles of water.

Thus, 0.34 moles of oxygen will give 2 × 0.34 moles

                                                 = 0.67 moles of water.

Mass of water = moles × molar mass

                    = 0.67 × 18

                    = 12.1 g of water

Therefore, 12.1 grams of water are produced when 5.38g of O₂ is reacted.

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Answer:

O3 => CLO + O2

Explanation:

ozone gas yields one Chlorine Monoxide gas, and two Oxygen gas. i forgot how to explain it well, but I know how to do it and will help in the future if needed :)

This problem is providing the mass of gummy bears which are assumed to contain 13 g of sucrose, which undergoes combustion and produces -214.3kJ of heat according to the following:

In chemistry, when a fuel undergoes combustion, a reaction with oxygen, it produces carbon dioxide and water in a complete combustion. In such a way, with the given reaction, we can write the heat of reaction as -11,286 kJ per mole of reaction:

[tex]\Delta H=-11,286\frac{kJ}{mol\ rxn}[/tex]

Which means that if we need the total heat released by 13 g of sucrose, one must apply the following dimensional analysis including this fuel's molar mass (342.3 g/mol):

[tex]Q=-11,286\frac{kJ}{mol\ rxn}*\frac{1mol\ rxn}{2molC_1_2H_2_2O_1_1}*13gC_1_2H_2_2O_1_1 *\frac{1molC_1_2H_2_2O_1_1}{342.3gC_1_2H_2_2O_1_1} \\\\Q=-214.3kJ[/tex]

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Answer:

[tex]2.82x10^{23}molecules[/tex]

Explanation:

Hello.

In this case, given the volume (1cm³=1mL) and density of the bromine we are to firstly compute the mass since it will allow us to compute the representative particles:

[tex]\rho =\frac{m}{V}[/tex]

[tex]m=\rho *V=3.12g/cm^3*24.0cm^3\\\\m=74.88gBr_2[/tex]

Next, since the mass of one mole of diatomic bromine is 159.82 g (one bromine weights 78.91), we can next compute the moles in that sample:

[tex]n=74.88g*\frac{1mol}{159.82g} =0.469molBr_2[/tex]

Finally, via the Avogadro's number we can compute the representative particles of bromine as follows:

[tex]particles=0.469mol*\frac{6.022x10^{23}molecules}{1mol}\\ \\2.82x10^{23}molecules[/tex]

Best regards.

Explanation:

Atomic number = 12

Block = s-block

Period = 3rd

Group = 2nd

The properly balanced chemical equation for this chemical reaction is written as follows:

                   [tex]FeCl_{3}(aq)+3Na0H(aq) \rightleftharpoons Fe(OH)_3(s)+3NaCl(aq)[/tex]

A chemical reaction can be defined as a chemical process that involves the continuous transformation (rearrangement) of the ionic, atomic or molecular structure of a chemical element by breaking down and forming chemical bonds, in order to produce a new chemical compound while new bonds are formed.

The chemical reaction of aqueous ferric hydroxide that is dissolved in aqueous sodium hydroxide produces ferric hydroxide and aqueous sodium chloride. Thus, the properly balanced chemical equation for this chemical reaction is written as follows:

                   [tex]FeCl_{3}(aq)+3Na0H(aq) \rightleftharpoons Fe(OH)_3(s)+3NaCl(aq)[/tex]

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Answer:

2 Mg(s) + O2(g)→ 2 MgO(s)

Explanation:

Number of moles of magnesium reacted = mass/ molar mass = 3.28g/24gmol-1 = 0.137 moles

From the balanced reaction equation;

2 moles of Mg yields 2 moles of MgO

0.137 moles of Mg yields 0.137 moles of MgO

For oxygen;

Number of moles of oxygen reacted = mass/ molar mass = 7.5g/32gmol-1 = 0.234 moles of O2

If 2_moles of oxygen yields 2 moles of MgO

0.234 moles of oxygen yields 0.234 moles of MgO

Hence Mg is the limiting reactant

Theoretical yield of MgO = 0.137 moles × 40 gmol-1 = 5.48 g of MgO

% yield of MgO = 83.7%

But

% yield = actual yield/theoretical yield × 100

actual yield = % yield × theoretical yield / 100

actual yield= 83.7 × 5.48/100

Actual yield = 4.59 g

According to the equation;

2 moles of Mg reacts with 2 moles of oxygen

Hence 0.137 moles of Mg will react with 0.137 moles of O2

Amount of excess reactant = 0.234 moles - 0.137 moles = 0.097 moles

Mass of excess reactant = 0.097 moles × 32gmol-1 = 3.1g of O2

The molar concentration of benzene is 0.05mol/L

Data;

molar mass of benzene = 78g/mol

molar mass of ethanol = 46g/mol

mole fraction of benzene is

[tex]mole fraction = \frac{moles of benzene}{total mole}[/tex]

Let's substitute the values and find the mole fraction of benzene

[tex]_yC_6H_6 = \frac{\frac{0.005}{78} }{(\frac{0.005}{78})+ (\frac{1-0.005}{46}) }\\ _yC_6H_6 = 0.00295[/tex]

The density of benzene given is 789 kg/m^3

Molar concentration of the solution is

[tex]M = \frac{789}{0.046} = 17.15Kmol/m^3[/tex]

The concentration of benzene is the product of mole fraction and the molar concentration of the solution

[tex]M = 0.00295 * 17.152 = 0.05Kmol/m^3= 0.05mol/L[/tex]

The molar concentration of benzene is 0.05mol/L

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Answer:

522

Explanation:

9 time 8 is 72, 7 carryover on 5 and 9 times 5 is 45 plus 7 carry over which is equal to 52. Therefore answer becomes 522.

Answer:

ill try

Explanation:

Answer:

a) equivalence point

b) direct titration

c) primary standard

d) titrand

e) Back titration

f) back titration

g) standard solution

h) standard solution

I) indirect titration

j) end point

Explanation:

A volumetric analysis is one in which a solution of unknown concentration is determined from its volume. This is commonly referred to as titration.

In titration, a standard solution is reacted with another solution of unknown concentration. The point at which the concentration of the standard solution is equal to that of the analyte is known as the equivalence point (usually indicated by a colour change). An indicator may be added to the analyte solution to help identify when the reaction is complete.

Explanation:

the formula of combined gas law = PV/T

:• PV/T = K

K is constant

Answer:

2835J

Explanation:

Q = mcΔT

Given,

Q = 45 × 4.2 × 15

Q = 2835 J

Answer:

The molar mass of N

2

is 28 g/mol.

56 grams of N

2

=

28g/mol

56g

=2moles

At STP, 1 mole of any gas occupies a volume of 22.4 L.

2 moles of N

2

at STP will occupy a volume of 2×22.4=44.8L

Answer:

Hear is the transfer of thermal energy between system.

Work is the transfer of mechanical energy between two systems.

Answer:

you gotta rotate it 90 degrees and get that screen fixed

Explanation:

Answer:

Explanation:

All forms of energy that may move in waves, including as light, x-rays, radio signals, heat, and microwaves, are included in the electromagnetic spectrum. These waves all have an abundance of energy in them. Additionally, they can all fly through outer space.

Light energy is a type of electromagnetic energy, while heat energy is a type of kinetic energy made up of the random motion of a material's particles. This is the main distinction among light energy and heat energy. Despite the fact that light and heat are both forms of energy, both are not the same. All forms of energy that may move in waves, including as light, heat, x-rays, radio signals, ultraviolet waves, and microwaves, are included in the electromagnetic spectrum. These waves all have an abundance of energy in them. Additionally, they can all fly through outer space.

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Answer:

1 grams Cl2 is equal to 0.014103178856514 mole.

Explanation:

Hope This Helps

Have A Great Day

Answer:

Please show a file so I can answer your question or tell me which experiment.

Explanation:

Definition:The control group (sometimes called a comparison group) is used in an experiment as a way to ensure that your experiment actually works. It's a way to make sure that the treatment you are giving is causing the experimental results, and not something outside the experiment.