K,Cro, + Pb(NO), - PbCro, * 2KNO,
If 25.0 grams of K,Cro, reacts to produce 20 grams of PbCroy, what is the
percent yield of PbCro?

pH of solution = 13.033

Given

2.31 g Ba(OH)₂

250 ml water

Required

pH of solution

Solution

Barium hydroxide is fully ionized, means that Ba(OH)₂ is a strong base

So we use a strong base formula to find the pH

[OH ⁻] = b. Mb where

b = number of OH⁻ /base valence

Mb = strong base concentration

Molarity of Ba(OH)₂(MW=171.34 g/mol) :

[tex]\tt M=\dfrac{mol}{L}=\dfrac{2.31~g\div 171.34~g/mol}{0.25~L}\\\\M=0.054[/tex]

Ba(OH)₂ ⇒ Ba²⁺ + 2OH⁻(b=valence=2)

[OH⁻]= 2 . 0.054

[OH⁻] = 0.108

pOH= - log 0.108

pOH=0.967

pOH+pH=14

pH=14-0.967

pH=13.033

STP = standard temperature and pressure

Use the formula:

d = MP/RT

where:

d = density = 1.25 g/L

M = molar mass (unknown)

P = pressure = 1 atm (standard pressure)

R = universal gas constant = 0.8206 L*atm/mol*K

T = temperature = 0C or 293.15 K (standard temperature)

1.25 g/L = M*(1 atm)/(0.08206 L*atm/mol*K)*(273.15 K)

M = 28.0 grams/mol

Answer:

6. O₂ + Cu —> CuO

7. H₂ + Fe₂O₃ —> H₂O + Fe

8. O₂ + H₂ — > H₂O

9. H₂S + NaOH —> Na₂S + H₂O

10. Al + HCl —> H₂ + AlCl₃

Explanation:

6. Oxygen gas react with solid copper metal to form copper(II) oxide

Oxygen gas => O₂

Copper => Cu

copper(II) oxide => CuO

The equation is:

O₂ + Cu —> CuO

7. hydrogen gas and iron(III) oxide powder react to form liquid water and solid iron power

hydrogen gas => H₂

Iron(III) oxide => Fe₂O₃

Water => H₂O

Iron => Fe

The equation is:

H₂ + Fe₂O₃ —> H₂O + Fe

8. Oxygen gas react with hydrogen gas to form liquid water

Oxygen gas => O₂

hydrogen gas => H₂

Water => H₂O

The equation is:

O₂ + H₂ — > H₂O

9. Hydrogen sulphide gas is bubbled through a sodium hydroxide solution to produce sodium sulphide and liquid water

hydrogen sulphide => H₂S

sodium hydroxide => NaOH

Sodium sulphide => Na₂S

Water => H₂O

The equation is:

H₂S + NaOH —> Na₂S + H₂O

10. Hydrogen gas and aluminum chloride solutions are produced when solid aluminum react with hydrochloric acid

Aluminum => Al

Hydrochloric acid => HCl

hydrogen gas => H₂

Aluminum chloride => AlCl₃

The equation is:

Al + HCl —> H₂ + AlCl₃

Answer:

Physical Weathering

Frost wedging. Frost wedging happens when water filling a crack freezes and expands (as it freezes, water expands 8 to 11% in volume over liquid water). ...

Heat/Cold Cycles. ...

Unloading

Explanation:

Answer:

heat transfer

Answer: I think its A? im not completely sure though!!

Explanation:

Answer:

a.cocentration es la respuesta

Answer:

the discovery of atomic structure.

Explanation:

Rutherford was a famous scientist who gave his theory of atomic structure.

Ernest Rutherford was a great physicist who is well known for his pioneering studies and discoveries about atoms and radioactivity. Rutherford was considered to be the greatest experimentalist after Michael Faraday.

Rutherford's atomic model was one of the greatest discoveries which provided many answers and solutions to the structure of atom and molecules that our earth is surrounded of.

Rutheford discovered that an atom has a tiny mass of positively charged particles in the centre of the atom called nucleus and negatively charged electrons surrounds the nucleus.

Bohr joined Rutherford in his studies and discovered many new facts about the structure of the atom based on the Rutherford's model. Today atomic model is the product of Rutherford atomic structure.

Answer:

(a)

[tex]v = 10.1mL[/tex] --- Silicon

[tex]v = 9.0mL[/tex] --- Tin

[tex]v = 7.5mL[/tex] -- Lead

(b)

[tex]d = 1.55g/mL[/tex] --- Silicon

[tex]d = 5.56g/mL[/tex] --- Tin

[tex]d = 9.53g/mL[/tex] --- Lead

Explanation:

Given

The attached table

Solving (a): The volume of each sample

For each element, the volume (v) is calculated as:

[tex]v = v_f - v_i[/tex]

Where:

[tex]v_f = Final\ Volume[/tex]

[tex]v_i = Initial\ Volume[/tex]

So, we have:

Silicon:

[tex]v_f = 40.1mL;\ \ \ v_i = 30.0mL[/tex]

So, we have:

[tex]v = 40.1mL - 30.0mL[/tex]

[tex]v = 10.1mL[/tex]

Tin:

[tex]v_f = 29.0mL;\ \ \ v_i = 20.0mL[/tex]

So, we have:

[tex]v = 29.0mL - 20.0mL[/tex]

[tex]v = 9.0mL[/tex]

Lead:

[tex]v_f = 33.5mL;\ \ \ v_i = 26.0mL[/tex]

So, we have:

[tex]v = 33.5mL - 26.0mL[/tex]

[tex]v = 7.5mL[/tex]

Solving (b): The density of each sample

For each element, the density (d) is calculated as:

[tex]d = \frac{m}{v}[/tex]

Where

[tex]m = mass[/tex]

[tex]v = volume[/tex]

So, we have:

Silicon:

[tex]m = 15.70g[/tex]

[tex]v = 10.1mL[/tex] --- calculated in (a)

Density (d):

[tex]d = \frac{15.70g}{10.1mL}[/tex]

[tex]d = 1.55g/mL[/tex]

Tin:

[tex]m = 50.07g[/tex]

[tex]v = 9.0mL[/tex] --- calculated in (a)

Density (d):

[tex]d = \frac{50.07g}{9.0mL}[/tex]

[tex]d = 5.56g/mL[/tex]

Lead:

[tex]m = 71.47g[/tex]

[tex]v = 7.5mL[/tex] --- calculated in (a)

Density (d):

[tex]d = \frac{71.47g}{7.5mL}[/tex]

[tex]d = 9.53g/mL[/tex]

The molar concentration of the original HF  solution : 0.342 M

Given

31.2 ml of 0.200 M NaOH

18.2 ml of HF

Required

The molar concentration of HF

Solution

Titration formula

M₁V₁n₁=M₂V₂n₂

n=acid/base valence (amount of H⁺/OH⁻, for NaOH and HF n =1)

Input the value :

[tex]\tt 0.2\times 31.2\times 1=M_2\times 18.25\times 1\\\\M_2=0.342[/tex]

Answer: Non-polar covalent bond

Explanation: If two atoms have no difference between their electronegativity charges, they will form nonpolar covalent bonds. This means that the electrons will be shared with the same intensity.

1.4 mol CO

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Atomic Structure

Stoichiometry

Step 1: Define

8.5 × 10²³ molecules CO

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

Step 4: Check

Follow sig fig rules and round. We are given 2 sig figs.

1.41149 mol CO ≈ 1.4 mol CO

Answer:

c ) 8

Explanation:

Given data:

Number of moles of water produced = ?

Moles of hydrogen react = 8 mol

Solution:

Chemical equation:

2H₂ + O₂     →     2H₂O

Now we will compare the moles of hydrogen and water.

         H₂          :         H₂O

          2          :            2

         8           :           8

Thus, 8 moles of water will produced.

Answer:

B

Explanation:

Just took the test

Answer:

b

Explanation:

edge 2021

Answer:

1) Mass = 18.864 g

2) V =  2.47 L

Explanation:

1) Given data:

Mass of water produced = ?

Mass of SnO₂ react = 79.0 g

Solution:

SnO₂ + 2H₂   →      Sn + 2H₂O

Number of moles of SnO₂:

Number of moles = mass/molar mass

Number of moles = 79.0 g/ 150.71 g/mol

Number of moles = 0.524mol

Now we will compare the moles of SnO₂ and H₂O

                 SnO₂         :        H₂O

                    1             :          2

                  0.524      :         2/1×0.524 =1.048 mol

Mass of water:

Mass = number of moles × molar mass

Mass = 1.048 mol × 18 g/mol

Mass = 18.864 g

2) Given data:

Volume of oxygen required = ?

Volume of C₃H₈ combust at STP = 0.499 L

Solution:

Chemical equation:

C₃H₈ + 5O₂     →      3CO₂ + 4H₂O

Number of moles of C₃H₈:

PV = nRT

R = general gas constant = 0.0821 atm.L /mol.K

1 atm × 0.499 L = n × 0.0821 atm.L /mol.K × 273.15 K

0.499 L atm.L = n × 22.43 atm.L /mol

n = 0.499 L atm.L / 22.43 atm.L /mol

n = 0.022 mol

Now we will compare the moles of propane and oxygen.

                  C₃H₈        :           O₂

                       1          :           5

                    0.022    :          5/1×0.022 = 0.11 mol

Volume of oxygen required:

PV = nRT

R = general gas constant = 0.0821 atm.L /mol.K

1 atm ×  V = 0.11 mol × 0.0821 atm.L /mol.K × 273.15 K

1 atm ×  V  = 2.47 atm.L

V = 2.47 atm.L  / 1 atm

V =  2.47 L

Answer:

39.13

Explanation:

To find that atomic mass of this potassium, we follow the steps below:

 Given parameters:

Abundance of K - 39  = 93.26%

Mass of K - 39  = 39

Abundance of K - 41  = 6.73%

Mass of K - 41 = 41

To find the average atomic mass;

Average atomic mass  =( mass x abundance of k -39 ) +( mass abundance of k- 41)

Average atomic mass =  (39 x  93.26%) + (41 x6.73%  )  = 39.13

Answer:

V₂ = 46.34 mL

Explanation:

Given data:

Initial temperature = 273 K

Initial volume = 50.0 mL

Final temperature = 253 K

Final volume = ?

Solution:

The given problem will be solve through the Charles Law.

Charles Law

"The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure"

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume  

T₂ = Final temperature

by putting values in formula,

V₁/T₁ = V₂/T₂

V₂ = V₁T₂/T₁  

V₂ = 50.0 mL × 253 K / 273 k

V₂ = 12650 mL.K / 273 K

V₂ = 46.34mL

Answer:

2nd option

Explanation:

Answer:

The answer is A.

Explanation:

The answer is A because it is talking about a living organism.

Hope this helps! :)

Answer: A. 20.0L

Explanation:

According to avogadro's law, equal moles of all gases occupy equal volumes at STP.

The given balanced equation is:

[tex]2C_2H_2(g)+5O_2(g)\rightarrow 2H_2O(g)+4CO_2(g)[/tex]

According to stoichiometry :

4 L of [tex]CO_2[/tex] is formed by = 2 L of [tex]C_2H_2[/tex]

Thus 40.0 L  of [tex]CO_2[/tex] is formed by = [tex]\frac{2 L}{4L}\times 40.0L=20.0L[/tex] of [tex]C_2H_2[/tex]

Thus 20.0 L of [tex]C_2H_2[/tex] is required to form 40.0L  of [tex]CO_2[/tex]

Answer:

Explanation:

can someone help me out here i can’t see the answer

Answer:

The Earth's orbit is an ellipse.

Explanation:

The Earth's orbit is not a perfect circle. It is elliptical, or slightly oval-shaped.

Earth's Rotation causes day and night.

The Moon goes around Earth. The Earth goes around the sun.

Answer:

The mass of an atom is equal to the protons plus the neutrons

Explanation:

The group number in the periodic table represents number of valence electrons of the elements in a certain group.

Group 1 : 2,8,1

Group 2 : 2,8,8,2

Group 3 : 2,8,3

Group 4: 2,4

Group 7 : 2,8,7

Answer:

 2, 8 7                7 valence electrons        Group 7

 2, 8 , 1              1 valence electrons         Group 1

 2 8 3               3 valence electrons         Group 3

  2  4               4 valence electrons         Group 4

 2 8 8 2            2 valence electrons         Group 2

Explanation:

The valency of an electronic configuration of an atom can be used to determine the group an element belongs.

The valency is the number of outermost shell electrons an atom contains.

 So;

 2, 8 7                7 valence electrons        Group 7

 2, 8 , 1              1 valence electrons         Group 1

 2 8 3               3 valence electrons         Group 3

  2  4               4 valence electrons         Group 4

 2 8 8 2            2 valence electrons         Group 2

Answer:

Gravity is viewed as a force because it is a force. A force F is something that makes objects of mass m accelerate according to F=ma. ... Einstein explained this gravitational force, F=GMm/r2, as a consequence of the curved spacetime around the massive objects.

Explanation:

Gravity is viewed as a force because it is a force. A force F is something that makes objects of mass m accelerate according to F=ma. ... Einstein explained this gravitational force, F=GMm/r2, as a consequence of the curved spacetime around the massive objects.

Answer:

Hydrogen Peroxide

Explanation:

Answer:

Hydrogen Peroxide

Hope this helps.

Explanation:

Answer:

C - Wind

Explanation:

its C or wind because global wind systems control the surface water

Answer:

Wind

Explanation:

surface water from oceans move from the wind I assume it is the same for all bodies of water

Answer:

A. carrots look better when given more water