PLEASE HELP!! 74 POINTS
An igneous rock has small, dark crystals. Which statement also accurately describes this rock?

It is an intrusive rock.
It has a coarse texture.
It was found on Earth’s surface.
It was formed from slow cooling.
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Which is one factor that contributes to the formation of polar, temperate, and tropical zones?

the angle of the Sun’s rays
the direction of seasonal winds
the presence of prevailing winds
the movement of wind near a mountain

Answer:

See explanation

Explanation:

The organic layer is always found at the top of the mixture while the aqueous layer is found at the bottom of the mixture.

Therefore, if I use any piece of rod and an empty container found in the kitchen to perform a simple decantation, the top layer that comes out first is the organic layer. The other layer that remains after the top layer has been successfully decanted is the aqueous layer.

The answer is a                                  bevasue it then becomes a chemical compound

Answer:

a

Explanation:

this would result in a compound and compounds are chemical changes so i think im right....

Answer:

POCl3

Explanation:

A compound is a substance made up of atoms of different elements. The number of atoms each element posseses make up the chemical formula of the compound. In this question, a certain compound is made up of three chlorine atoms (Cl3), one phosphorus atom (P), and one oxygen atom (O).

Combining these atoms of different quantity together, this means that the compound will have a chemical formula: POCl3. This compound is called phosphorus oxychloride.

Answer:

3. NH3 is limiting

4. 90 g NO

Explanation:

3. To find the limiting reactant, you have to convert from moles of reactant to moles of product. In this case, because we need to know how many grams of NO in the second question, we will use NO as our product. We use the ratios found in the chemical formula.

[tex]3 mol NH3*\frac{4 molNO}{4 mol NH3} = 3molNO[/tex]

[tex]6 mol O2*\frac{4 molNO}{5 mol O2} = 4.8molNO[/tex]

Because NH3 makes less moles of NO, it is the limiting reactant.

4. Now we need the molar mass to convert the moles of NO into grams of NO. The molar mass of NO is 30.01g/mol. This is the equation.

[tex]3 mol NO*\frac{30.01g NO}{1 mol NO} = 90.03gNO[/tex]

Because there are is only one significant figure in the original numbers, we round to one significant figure = 90 g NO.

Answer: [tex]Pb(NO_3)_2(aq)+2NaOH(aq)\rightarrow 2NaNO_3(aq)+Pb(OH)_2(s)[/tex]

Explanation:

A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.

The balanced chemical equation for a precipitate forms when aqueous solutions of lead(II) nitrate and sodium hydroxide are combined is:

[tex]Pb(NO_3)_2(aq)+2NaOH(aq)\rightarrow 2NaNO_3(aq)+Pb(OH)_2(s)[/tex]

Answer:

Ion

Explanation:

Answer:

Conclusión. Los cationes son iones con carga positiva que se forman cuando los átomos neutros pierden electrones; los aniones son iones con carga negativa que se forman cuando átomos neutros ganan electrones.

Explanation:

Answer:

Mass = 2304 g

Explanation:

Given data;

Number of atoms of oxygen = 8.65×10²⁵

Mass in gram = ?

Solution:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.  The number 6.022 × 10²³ is called Avogadro number.

For example,

1 mole = 6.022 × 10²³ atoms

8.65×10²⁵ atoms of oxygen× 1mol  /6.022 × 10²³ atoms

1.44×10² mol

144 mol

Mass in grams of oxygen:

Mass = number of moles × molar mass

Mass = 144 mol × 16 g/mol

Mass = 2304 g

Answer:

try dividing the grams and the volume and see what number matches up with your answer

Answer:

acidic because of electrical issues and the body of electrical equipment

Answer:

Mass of glucose = 515.34 g

Explanation:

We are given;

Mass; m = 60 kg

Elevation; h = 1550 m

Acceleration due to gravity; 9.8 m/s²

Now, work performed to lift 60kg by 1550m is given by the formula;

W = mgh

W = 60 × 9.8 × 1550

W = 911400 J

We are told the actual work is 4 times the one above.

Thus;

Actual work = 4W = 4 × 911400 = 3,645,600 J

Now,

Molar mass of Glucose(C6H12O6) = 180 g/mol

We are given standard enthalpy of combustion = -1273.3 KJ/mol = -1273300

Moles of glucose = 3645600/1273300 = 2.863mol

Mass of glucose = 2.863 mol × 180 g/mol

Mass of glucose = 515.34 g

Answer:

Kinetic Energy is the correct Answer.

Explanation:

At the highest point on the roller coaster (assuming it has no velocity), the object has a maximum quantity of gravitational potential energy. As the object begins moving down to the bottom, its gravitational potential energy begins to decrease and the Kinetic Energy starts to increase.

Answer:

Cave Crystal

Explanation:

I believe it's cave crystal because sand dunes, river deltas, and valleys are all examples of deposition.

Explanation:

It represent Alcohol group (—OH)

Answer:

The molecules in the liquid are moving past one another. The hydrogen end of one water molecule is attracted to the oxygen end of another but only for a short time because they are moving. The molecules in ice are further apart than in liquid water. The molecules in ice are in fixed positions but still vibrate.

Explanation:

-google

Answer:

[tex]5.412*10^{23}[/tex]

Explanation:

We can find the moles of lithium by doing 0.0624 divided by the molar mass of lithium (which is 6.941). Then, we can multiply that number by 6.02*10^23 which is the avogadro number. Then, we get our answer.

Ideal gas law is valid only for ideal gas not for vanderwaal gas. Therefore, value of the gas constant R is 0.0821LatmK⁻¹ when volume is 0.0413 L.

Ideal gas equation is the mathematical expression that relates pressure volume and temperature.

Mathematically the relation between Pressure, volume and temperature can be given as

PV=nRT

where,

P = pressure of nitrogen gas = 0.991 atm

V= volume of nitrogen gas =0.0413 L

n =number of moles of nitrogen gas = given mass ÷Molar mass

                                                          =0.0451 g ÷28

                                                          =0.0016mol

T =temperature of nitrogen gas =298 K

R = Gas constant =?

0.991 atm×0.0413 L=0.0016×R×298 K

R=0.0821LatmK⁻¹

Therefore, value of the gas constant R is 0.0821LatmK⁻¹.

To learn more about ideal gas equation, here:

https://brainly.com/question/14826347

#SPJ2

Answer:

1.88 × 10²⁴ atoms

Explanation:

Step 1: Given data

Mass of sulfur: 100 g

Step 2: Calculate the moles corresponding to 100 g of sulfur

The molar mass of sulfur is 32.07 g/mol. The moles corresponding to 100 g of sulfur are:

100 g × (1 mol/32.07 g) = 3.12 mol

Step 3: Calculate the number of atoms in 3.12 moles of sulfur

We will use Avogadro's number: there are 6.02 × 10²³ atoms of sulfur in 1 mole of sulfur.

3.12 mol × (6.02 × 10²³ atoms/1 mol) = 1.88 × 10²⁴ atoms

Complete Question

The complete question is shown in the first uploaded image

Answer:

So the math expression is  

             [tex]heat  =  \frac{ 35. 7  KJ *  1900 \ gram }{ 1 \ gram }[/tex]

Explanation:

From the question we are told that

  The heat released for 1 gram of reactant consumed is  [tex]H  =  37.5 \ KJ/g [/tex]

   The mass of reactant considered is  [tex]m =  1.9 \ kg  =  1900 \  g[/tex]

So  if

             [tex]37.5 \ KJ [/tex] is produced for  1 gram

Then

              x kJ is produced for  1900 g  

=>   [tex]x  =  \frac{ 35. 7  KJ *  1900 \ gram }{ 1 \ gram }[/tex]

So the heat released is  

       [tex]heat  =  \frac{ 35. 7  KJ *  1900 \ gram }{ 1 \ gram }[/tex]

Answer:

x = 33.52 amu

Explanation:

It is given that,

Isotope A has a mass of 34 amu and an abundance of 52%, isotope B has a mass of 33 amu and an abundance of 48%.

Let x is the average atomic mass of this element. It can be calculated as follows :

[tex]x=52\%\ \text{of}\ 34+48\%\ \text{of}\ 33\\\\x=\dfrac{52}{100}\times 34+\dfrac{48}{100}\times 33\\\\x=0.52\times 34+0.48\times 33\\\\x=33.52\ \text{amu}[/tex]

So, the average atomic mass of this element is 33.52 amu.

Answer:

See explanation

Explanation:

∆H is known as the change in enthalpy. When the change in enthalpy is negative, it simply means that heat is given out during the reaction. Therefore, we refer to the reaction as an exothermic reaction.

Similarly, ∆G is known as change in free energy. When the change in free energy is negative, it implies that the reaction is spontaneous as written. This is called an exergonic reaction.

Answer:

I think option D

I hope my answer is helpful to you

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Answer:

Explanation:

Let n be number of half lives taken .

10 = 70 x ( 1/2 )ⁿ

1/7 = ( 1/2 )ⁿ

2ⁿ = 7

n ln2 = ln 7

n = ln7 / ln2

= 1.9459 / .693

= 2.8

So 2.8 half lives will be required .

Answer:

They show that the number of atoms of each  element is the same in the products and  reactants

Explanation:

Balanced chemical equations show the conservation of mass in that the number of atoms of each element is the same in the products and reactants.

Answer:

C (They show that the number of atoms of each element is the same in the products and reactants.)

For the next question: C (2H2(g) + O2(g) → 2H2O(g))

Explanation:

For Edge

Answer:

The equilibrium concentration of IBr is 0.0360 M or 0.1032 M

The equilibrium concentration of IBr is 0.752 mol

Explanation:

Mathematically, concentration = number of moles/volume

For Iodine molecule, concentration = 0.2/5 = 0.04 M

For the bromine molecule, concentration = 0.1/5 = 0.02 M

We need to set up an ICE table ( Initial, change, equilibrium)  to get the concentrations of the molecules at equilibrium.

Please check this table in the attachment.

From the table, we can see that the equilibrium concentration of Iodine is (0.04-x), that of Bromine is (0.02-x) while that of IBr is 2x

Now, we need to get the equilibrium constant  using the equilibrium concentration of the molecules

With the given chemical reaction, we can represent the equilibrium constant in terms of pressure as follows;

Kc = [IBr]^2/[Br2][I2]

Thus;

Kc = (2x)^2/(0.04-x)(0.02-x)

Kc = 4x^2/(0.04-x)(0.02-x)

From the question, Kc = 29 , so substitute this;

29 = 4x^2/(x^2-0.06x+0.008)

Cross multiply

29((x^2-0.06x+0.008) = 4x^2

29x^2 - 1.74x +0.0232 = 4x^2

Thus;

25x^2 - 1.74x + 0.0232 = 0

Solving this quadratic equation, we get two values for x which are x = 0.0516 and 0.0180

The equilibrium concentration is either (2 * 0.018) or (2 * 0.0516) which is 0.0360 or 0.1032

Answer:

Several extractions is more effective than a single extraction.

Explanation:

When extraction is carried out multiple times, for instance, in this case, the extraction was carried out with three portions of the solvent rather than with just a single portion of the solvent, the amount of material left in the residue will be lower, because the extraction is more complete.

Several extractions with smaller volumes of solvent are more effective than a single extraction with a large volume of solvent.

Answer:

+0.02 V

Explanation:

For the reaction to be spontaneous, iron must be the cathode and Mercury the anode

Given that the standard cell potential is obtained from;

E°=E° cathode - E° anode

Since;

E° cathode = -0.77V

E° anode = 0.79 V

E°cell = -0.77 -(-0.79)

E°cell = +0.02 V