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Chromium exhibits a wide range of possible oxidation states, where the +3 state is the most stable energetically. The +3 and +6 states are the most commonly observed in chromium compounds, whereas the +1, +4 and +5 states are rare.

Answer:

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Due to the fact that electrons are delocalized in graphite, it is a good conductor of electricity. Carbon atoms in graphite form hexagonal layers and are in covalent bonds with three other carbon atoms. Due to this non-bond electron configuration, each carbon atom conducts electricity in the form of a delocalized electron.

Answer:

Calcium Nitrate is made up of three different elements and contains a total of nine atoms. This compound's formula is Ca(NO3)2. There is one calcium atom, two nitrogen atoms, and there are six oxygen atoms in calcium nitrate

Answer:

3.

Explanation:

potassium

bromine

oxygen

Answer:

So, the melting of wax and vapourisation of melted wax are physical changes. Chemical Changes : The wax near flame burns and gives new substances like carbon dioxide, carbon soot, water vapour, heat and light. LPG is another example of a familiar process in which both the chemical and physical changes take place.

Answer:

what the model is describing is the molecules. when molecules are tightly packed they form a solid like ice, and when the ice is melting forms a liquid because the molecules are spreading out. when the ice evaporates (gas) the molecules are moving about and are not touching eachother

[tex]\\ \sf\longmapsto Volume=\dfrac{Mass}{Density}[/tex]

[tex]\\ \sf\longmapsto Volume=\dfrac{212}{0.85}[/tex]

[tex]\\ \sf\longmapsto Volume=249.4mL[/tex]

Answer:

[tex]249.41 \: ml[/tex]

Explanation:

[tex]volume = \frac{mass}{density} \\ = \frac{212g}{0.85 \: g \: {ml}^{ - 1} } \\ = 249.41 \: ml[/tex]

Hope this helps you.

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Answer:There are two main exceptions to electron configuration: chromium and copper. See below

Explanation:

These two elements are exceptions because it is easier for them to remove a 4s electron and bring it to the 3d subshell, which will give them a half filled or completely filled subshell, creating more stability.

Answer:

5.2M, 5M, 0.975M, 28M

Explanation:

M = ( moles × 1000 ) ÷ volume

Molarity is affected by temperature. Its unit is mole/litre. It measure the concentration of any solute in a solution. Thus the molarity of [tex]KNO_{3}[/tex],[tex]BaCl_{2}[/tex],[tex]Na_{2}CO_{3}[/tex] and[tex]C_{6}H_{12}O_{6}[/tex] are 5.2mol/litre, 5mol/litre, 0.97mol/litre, 28mol/litre respectively.

Molarity can be calculated by dividing  number of moles of solute by volume of solution in liter.

Other concentration terms are molality, normality and mole fraction. Molarity can be used to find out the ionic strength of any solution

Mathematically,

Molarity= number of moles of solute/volume of solution in litre (1)

1) Molarity of [tex]KNO_{3}[/tex]= {1.30 mol ×(1000ml/l)}÷250.0 mL=5.2mol/litre

2)Molarity of [tex]BaCl_{2}[/tex]= {0.500 mol  ×(1000ml/l)}÷100.0 mL=5mol/litre

3)Molarity of[tex]Na_{2}CO_{3}[/tex]= {0.195 mol   ×(1000ml/l)}÷200.0 mL=0.97mol/litre

4)Molarity of [tex]C_{6}H_{12}O_{6}[/tex] = {7.00 mol  ×(1000ml/l)}÷ 250.0 mL=28mol/litre

Thus the molarity of [tex]KNO_{3}[/tex],[tex]BaCl_{2}[/tex],[tex]Na_{2}CO_{3}[/tex] and[tex]C_{6}H_{12}O_{6}[/tex] are 5.2mol/liter, 5mol/litre, 0.97mol/litre, 28mol/litre respectively.

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Answer:

8)Dinitrogen tetraoxide

9)+5

10)NH4HSO4

Explanation:

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Answer:

b. 39 Neutrons would be correct.

Explanation:

18 A

19 C

20 C

22 A

24 B

hope this helps you.

Answer:

1)A moth bursting out of a cocoon is neither a chemical or physical change, it's a biological change.  If I had to chose it would be a physical change though.  Not to sure...

2)Playing with slime is a physical change.  

Explanation:

1)The reason why I would chose physical change is because the moth is changing it's physical state more than it's chemical composition, but you should say both if that's an option.  

2)A physical change is when the temperature, shape, or state of matter changes. A chemical change occurs when the actual substance changes.  An example of this is a chemical reaction.  Because the slime is changing shape and not substances, I would say that it's obviously a physical change.  

Hope this helps, sorry that I'm not too sure about the 1st question.  

Answer:

From Middle school to college

Orange Juice is a heterogeneous mixture. This means the orange juice contains more than one component.

This is true because orange juice contains two components. They are:

The reason why the pulp in orange juice sinks to the bottom is because the pulp is denser than the juice. So it is heavier and sinks to the bottom.

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Answer:

1.6 M.

Explanation:

We want to find the molarity of a solution that contains 114.4 g NaCl in a 1.2 L solution.

Recall that molarity is given by:

[tex]\displaystyle \text{M} = \frac{\text{ mols solute}}{\text{ L soln.}}[/tex]

Convert 114.4 g NaCl to mol NaCl using its molecular weight:

[tex]\displaystyle 114.4 \text{ g NaCl} \cdot \frac{1 \text{ mol NaCl}}{58.44 \text{ g NaCl}} = 1.958\text{ mol NaCl}[/tex]

Therefore, the molarity of the solution will be:

[tex]\displaystyle \text{M} = \frac{1.958 \text{ mol NaCl}}{1.2\text{ L soln.}} = 1.6 \text{ M}[/tex]

In conclusion, the molarity of the solution is 1.6 M.

Answer:

t5gbt 4 tbg3rvb tjj5tb4b4bv

Explanation:fhtb v4bvtvhbvv bh

Answer:

a person or persons murder

Answer: the aerodynamics of hummingbird wings.

Explanation: i got it right

The volume, in liters, per kg of the Himalayan pink salt would be 0.97 L

Recall that: density = mass/volume

Hence: volume = mass/density

In this case, the density of the Himalayan pink salt is 1.03 while the mass we are working with is 1 kg.

1 kg is equivalent to 1000 g

Thus: volume = 1000/1.03

                           = 970.87 mL

Divide by 1000 to convert to L

                        970.87/1000 = 0.97 L

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Gasoline in water = insoluble

acetone in nail polished = soluble

salt in alcohol = soluble

oil in vinegar = insoluble

tawas in water = soluble...

Sorry if i am incorrect......

Answer:

4.76

Explanation:

Answer:

Changes of state are physical changes. They occur when matter absorbs or loses energy. Processes in which matter changes between liquid and solid states are freezing and melting. Processes in which matter changes between liquid and gaseous states are vaporization, evaporation, and condensation.

hope this helped

Answer:

Solid

Explanation:

According to Wikipedia

Deposition is the phase transition in which gas transforms into solid without passing through the liquid phase. Deposition is a thermodynamic process. The reverse of deposition is sublimation and hence sometimes deposition is called desublimation.

The gas that is to be identified in the problem is C2H2

From the ideal gas equation;

PV = nRT

P = pressure of the gas = 745 torr or 0.98 atm

V = volume of the gas =  4.13 mL or 0.00413 L

n = number of moles of the gas = ?

R = gas constant = 0.082 atm Lmol-1K-1

T = temperature of the gas = 23°C + 273 = 296 K

n = PV/RT

n = 0.98 atm ×  0.00413 L/0.082 atm Lmol-1K-1 × 296 K

n = 0.00405/24.272

n = 0.000167 moles

Recall that;

Number of moles = mass/molar mass

molar mass = mass/Number of moles

molar mass = 0.00500-gram/0.000167 moles

molar mass = 30 g/mol

Since it is a hydrocarbon;

[12 +1]n = 30

n = 30/13

n = 2

The gas is C2H2

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The mass of KOH reacted is 2.576 g. To have a 10% excess KOH, i need 2.833 g of KOH.

The equation of the reaction is;

2 Al(s) + 2 KOH(aq) + 6H20 (l) --------> 2K+ (aq) + 2 Al(OH)4^- (aq) + 3H2(g)

We are told that 1.25 g of Al was used in the reaction, hence;

Number of moles of Al = 1.25 g/27 g/mol = 0.046 moles

To obtain the amount of KOH required for the reaction;

2 moles of Al reacts with 2 moles of KOH

0.046 moles of Al also reacts with 0.046 moles of KOH

Mass of KOH reacted = 0.046 moles of KOH × 56 g/mol = 2.576 g

To have a 10% excess KOH;

Let the needed mass of KOH be x

x =2.576 g + (0.1 × 2.576 g)

x = 2.833 g

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Assuming you start with 1.25 g of pure aluminum, calculate the following:

Answer:

Conduction is between solids, convention is between liquid and radiation between the sun and a body on the earth

Answer:

In conduction, heat transfer takes place between objects by direct contact. In convection, the heat transfer takes within the fluid. In radiation, heat transfer occurs through electromagnetic waves without involving particles. ... The heat transfer occurs through a heated solid object.

Explanation:

Explanation:

thermoplastic polymer

Answer:

 A Chart Of The Chemical Elements That Displays Them In Rows Horizontally In Order Of Increasing Atomic Number And Vertically According To Similarity Of The Chemical Properties Of Their Atoms.