What are half-reactions?
O A. Equations showing which elements are oxidized and which are
reduced
O B. Equations showing the electronegativities of atoms in a reaction
O C. Equations showing what compounds are involved in a reaction
O D. Equations showing only the ions involved in a net ionic equation

Answer:

I think C but it could be D

Explanation:

I would say go for C

Answer:  1. magnesium hydroxide + sulfuric acid = magnesium sulphate + water

2. calcium hydroxide + hydrochloric acid = calcium  chloride + water

3. lead hydroxide + nitric acid =  lead nitrate + water

4. sodium hydroxide + sulfuric acid  =  sodium sulphate + water

5. potassium hydroxide + citric acid = potassium  citrate + water

6. silver hydroxide + hydrochloric acid = silver chloride + water

7.  aluminium hydroxide + phosphoric acid = aluminium phosphate + water

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 equations are :

1. magnesium hydroxide + sulfuric acid = magnesium sulphate + water

[tex]Mg(OH)_2(aq)+H_2SO_4(aq)\rightarrow MgSO_4(aq)+2H_2O(l)[/tex]

2. calcium hydroxide + hydrochloric acid = calcium  chloride + water

[tex]Ca(OH)_2(aq)+2HCl(aq)\rightarrow CaCl_2(aq)+2H_2O(l)[/tex]

3. lead hydroxide + nitric acid =  lead nitrate + water

[tex]Pb(OH)_2(aq)+2HNO_3(aq)\rightarrow Pb(NO_3)_2(aq)+2H_2O(aq)[/tex]

4. sodium hydroxide + sulfuric acid  =  sodium sulphate + water

[tex]NaOH(aq)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+H_2O(l)[/tex]

5. potassium hydroxide + citric acid = potassium  citrate + water

[tex]KOH(aq)+C_6H_8O_7(aq)\rightarrow C_6H_7O_7K(aq)+H_2O(l)[/tex]

6. silver hydroxide + hydrochloric acid = silver chloride + water

[tex]AgOH(aq)+HCl(aq)\rightarrow AgCl(s)+H_2O(l)[/tex]

7.  aluminium hydroxide + phosphoric acid = aluminium phosphate + water

[tex]Al(OH)_3(aq)+H_3PO_4(aq)\rightarrow AlPO_4(aq)+3H_2O(l)[/tex]

Answer:

. magnesium hydroxide + sulfuric acid = magnesium sulphate + water

2. calcium hydroxide + hydrochloric acid = calcium  chloride + water

3. lead hydroxide + nitric acid =  lead nitrate + water

4. sodium hydroxide + sulfuric acid  =  sodium sulphate + water

5. potassium hydroxide + citric acid = potassium  citrate + water

6. silver hydroxide + hydrochloric acid = silver chloride + water

7.  aluminium hydroxide + phosphoric acid = aluminium phosphate + water

Explanation:

is the answer llllllll

Answer:

108.3kPa

Explanation:

Given parameters:

Initial temperature  = 76k

Initial pressure  = 78.4kPa

Final temperature  = 105k

Unknown:

Final or new pressure  = ?

Solution:

To solve this problem, we apply the combined gas law:

           [tex]\frac{P_{1} }{T_{1} }[/tex]     =    [tex]\frac{P_{2} }{T_{2} }[/tex]

T1 = 76k

P1  = 78.4kPa

T2  = 105k

     [tex]\frac{78.4}{76}[/tex]   = [tex]\frac{P_{2} }{105}[/tex]  

     P2 = 108.3atm

Answer:

1/8

Explanation:

Use logic,

every one hour, half of a radioactive remains

for the first hour, half remains

for the second hour, half of half remains or quarter remains

for the third hour, 1/2 of 1/2 of 1/2 or 1/8 remains

or use this equation

[tex]n = r ({ \frac{1}{2} })^{ \frac{f}{t} } [/tex]

where

n = amount after f time

r = amount of the original isotope

f = time

t = half-life

Answer:

2.No. because in an open system, gas will blow up & so, if it's measured, it won't have the equal amount of the reactant. But, if you arrange this reaction in a closed system, then it will be the same.

3.2SiO2+4Cl2= 2SiCl4+O2

Explanation:

Answer:

protons and neutrons are the answer

Answer:

The object has to move a distance when a force is applied to it

Explanation:

For work to be done on a body the force applied must move the body through a particular distance.

  Work done  = Force x distance  

If no distance is moved by the force, no work is done.

Also, the angle between the force and the distance must be 0 to do the maximum work on the body.

Answer:

no

Explanation:

An empirical shows the simplest ratio among atoms in a compound .

Answer:

Radio wave

Explanation:

Radio waves are a type of electromagnetic wave radiation with wavelengths in the electromagnetic spectrum longer than infrared light

A seismic wave is an elastic wave generated by an impulse such as an earthquake or an explosion.

Sound and water waves are mechanical waves; meaning, they require a medium to travel through.

Answer:

A

Explanation:

Answer: This law states that, despite chemical reactions or physical transformations, mass is conserved — that is, it cannot be created or destroyed — within an isolated system. In other words, in a chemical reaction, the mass of the products will always be equal to the mass of the reactants.

Answer:

A is 2, B is 8, and C is 18

Explanation:

I did the Gizmos

The two, eight, and eighteen electrons can be filled in the first, second, and third energy levels respectively.

The electrons revolve in different orbits are known as energy levels or stationary states. These energy levels are numbered as n = 1, 2, 3…… These values are also known as the principal quantum numbers.

The first energy level is also known as 'K' shell or level. The second energy level is called 'L' shell, the third energy level is 'M' shell, and so on.

The electrons present in the K shell contain the least energy whereas the levels contain more energy that is far from the nucleus.

The first energy level (n = 1) can have maximum two electrons in it. The second energy level ( n= 2) can have maximum eight electrons and the third energy level can fill maximum eighteen electrons in it.

Learn more about energy levels, here:

https://brainly.com/question/17396431

#SPJ5

Answer:

13 moles of oxygen

Explanation:

A mole of a substance is the unit of measuring the number of particles within a chemical substance.

The given compound is:

      Ca₅ (PO₄)₃OH

This is a mole of   Ca₅ (PO₄)₃OH

  In this compound we have:

  5 moles of Ca

  3 mole of P

   13 mole of O

   1 mole of H

So,

  In 1 mole of  Ca₅ (PO₄)₃OH, we have 13 moles of oxygen

Sample left = 6.25 g

The percentage = 6.25%

Given

t1/2 = half-life = 3.8 days

t = decay time = 15.2 days

No = initial sample = 100 g

Required

Nt = final sample left

The percentage

Solution

General formulas used in decay:  

[tex]\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}[/tex]

Input the value :

[tex]\tt N_t=100.\dfrac{1}{2}^{15.2/3.8}\\\\N_t=100.\dfrac{1}{2}^4\\\\N_t=6.25~g[/tex]

The percentage : Nt/No

6.25 : 100 = 6.25%

Answer:

I think the answer would be B. hope this helps!!

Explanation:

Answer:

c! Hope this helps!

Explanation:

BRAINLIEST PLZ ;)

Answer:

I think its the third one im not sure tho

Explanation:

Answer:

a, u cannot bend rocks

Explanation:

........yjmumtwjmyjy

Answer:

If the reaction requires energy, it is often indicated above the arrow. A capital Greek letter delta (Δ) is written on top of the reaction arrow to show that energy in the form of heat is added to the reaction; hv is written if the energy is added in the form of light.

Answer:

it means that to get the product, the reactants were heated

1. Find its coordination figure/coordination number of central atom (CF)

Ev = Vallence electron of central atom

Σe = electrons donated from substituents

Terminal O gives 0 electrons, hence Σe = 3 x 0

charge = charge of the compound

2. Find EP (electron pairs) and LP (lone pairs)

LP = CF - EP

3. Draw the skeleton with octet substituents (top right figure)

4. Find formal charge for each atoms (Qf)

5. Write formal charge near atom in skeleton

6. Enjoy

Answer:

A Infiltration

Explanation:

The downward movement of water through pore spaces and other spaces in soil due to gravity is called infiltration.

Infiltration is greatly due to the force of gravity forcing water through pore spaces downward.

Answer:

Sodium reacts more quickly, generating enough heat to melt itself and to occasionally ignite the hydrogen gas, producing a yellow-orange flame characteristic of sodium. The potassium reacts violently, immediately bursting into a flame which has the characteristic violet color of potassium.

Explanation:

Answer:

c

Explanation:

Answer:  The correct answer is:  " 0.54 g " .

__________________________________________

Explanation:

Note that "hydrogen gas" is:  

H₂ (g)  ;   that is:  a "diatomic element" (diatomic gas) ;

_________________________________________

The molecular weight of "H" is:  1.00794 g ;

   (From the Periodic Table of Elements).

So, the molecular weight of:  H₂ (g)  is:

    " 1.00794 g * 2  = 2.01588 g ; {use calculator) ;

_________________________________________

Note the conversion for a gas at STP:

______

  1 mol of a gas = 22.4 L gas;

___

i.e. " 1 mol / 22.4 L " ;

____

So:     " 5.7 L H₂ (g)  [tex]* \frac{1 mol H_{2} }{22.4 L} *\frac{2.01588 g}{mol} =? ;[/tex]

The "L" ("literes" cancel out to "1" ;  since "L/L = 1 ;

The "mol" (moles) cancel out to "1" ; since "mol/mol = 1 ;

____

and we are left with:

____

 [5.7 * 2.104588 g ] / 22.4  =  ?  g ;

______________________

→ [ 11.9961516  g ] / 22.4 =

          0.53554248214  g ;l

_____________________________

We round this value to:  " 0.54 g " ;

 → since "5.7 L " has 2 (two) significant figures;  

     22.4 is an exact number conversion;

     and "5.7 L" has fewer significant figures than:

    " 2.104588 " ; or:  " 1.00794 " .

  → as such: We round to "2 (two) significant figures."

______________________________

Hope this is helpful.  Wishing you the best in your academic endeavors!

_______________________________

Answer:

Brittle, Poor Conductors, Non-Malleable

Explanation:

Non-metals are the opposite of metals; they have opposite properties.

Metals are ductile, malleable, conductive, and shiny, while nonmetals are the opposite.

Answer:

C

Explanation:

Answer:

I think A, not sure

Explanation:

her weight depends on the force of gravity

Answer:2H₂+ O₂→ 2H₂O the reactants are 2H₂ and O₂ ... if the theoretical yield is 95 g of water after the chemical reaction you may have only 45g of water

i think

Explanation: