Answer:
1.55 x 10²⁴ formula units
Explanation:
Given parameters:
Number of moles of CaCl₂ = 2.58moles
Unknown:
Formula units in the compound = ?
Solution:
To solve this problem, we must understand that;
1 mole of a substance contains 6.02 x 10²³ formula units
2.58 moles will contain 2.58 x 6.02 x 10²³ formula units
= 1.55 x 10²⁴ formula units
2H₂ + O₂ -> 2H₂O In this equation, write the coefficient numbers
HELP ME PLEASEEEE
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:
SOMEONE HELP PLS ILL GIVE BRAINLIEST AND 19 PT
Sample left = 6.25 g
The percentage = 6.25%
Further explanationGiven
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%
For work to be done on an object:
*
The work input must be equal to the work output
The energy input must be equal to the energy output
Only a force must be applied, moving the object is not required
The object has to move a distance when a force is applied to it
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.
Types of osmosis...in 50 words
Osmosis is of two types:
Endosmosis– When a substance is placed in a hypotonic solution, the solvent molecules move inside the cell and the cell becomes turgid or undergoes deplasmolysis. This is known as endosmosis.
Exosmosis– When a substance is placed in a hypertonic solution, the solvent molecules move outside the cell and the cell becomes flaccid or undergoes plasmolysis. This is known as exosmosis.
There are some variations or types of osmosis on the basis of the direction of the movement of solvent molecules.
Reverse osmosis is a method of separation that is used to force a solvent through a semi-permeable membrane resulting in solute molecules on one side and solvent molecules on the other side.Reverse osmosis is different than the forward osmosis in that reverse osmosis utilized hydraulic pressure to force the solvent against the osmotic pressure.Forward osmosis is another variation of osmosis where the osmotic pressure gradient is used to induce the flow of water from the sample solution to separate the solutes.Forward osmosis uses a draw solution with a higher concentration of solute, which extracts the solvent molecules from the sample solution; thus, resulting in the separation of solute and solvent in the sample solution.Endosmosis is the movement of water into the cell which occurs when a cell is placed in a solution having a higher concentration of water than the cell.Exosmosis is the movement of water out of the cell which occurs when a cell is placed in a solution having a higher concentration of solute than the cell.
A gas at 76 K is under a pressure of 78.4 kPa. If the temperature changes to 105 what will be the new
pressure?
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
B
1. magnesium hydroxide + sulfuric acid sulfate +————
2. calcium hydroxide + hydrochloric acid calcium
+ water+————
3. lead hydroxide + nitric acid lead nitrate +————-
4. sodium hydroxide + sulfuric acid
+ water————-
5. potassium hydroxide + citric acid potassium
+ water————-
6. silver hydroxide + hydrochloric acid chloride +———
7. aluminium hydroxide + phosphoric acid———-
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
help me please just w number 2&3
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:
What is an empirical formula
An empirical shows the simplest ratio among atoms in a compound .
More informationan empirical formula is the simplest formula for a compound .For example, H2O2 can be reduced to a simpler formula. Determining a Molecular Formula from an Empirical Formula The empirical formula for a compound is P 2 O 5 . Its experimental molar mass is 284 g/mol.For example, the empirical formula of benzene (C5H5) is Qj, - because the mole ratio of carbon am'hydrogen is 1:1.What is the best way to make a supersaturated solution?
A. Heat the solution
B. Cool the solution
C. Stir the solution
D. Evaporate the solution
Answer:
A
Explanation:
Describe the relationship between an enzyme, substrate, and active site.
Which of the following is an example of an electromagnetic wave?
Seismic wave
Radio wave
Water wave
Sound wave?
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.
if the bending of rocks is to much what would happen? a. the rock will break
b. the rock will continue to fold
c. the rocks will be flattened
d. the rocks will build up an energy
Answer:
a, u cannot bend rocks
Explanation:
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what are three properties of non-metals
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.
What mass in grams would 5.7L of hydrogen gas occupy at STP?
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!
_______________________________
If you broke a mineral into smaller pieces, each piece would
A- have the same density B- have the same hardness
C- show the same cleavage pattern
D- All are correct
What does a triangle written above the arrow in an equation
represent?
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
Electrons are arranged in orbits called energy levels. The Gizmo shows all of the
first two energy levels but only part of the third energy level.
A. How many electrons can fit in the first energy level?
B. How many electrons can fit in the second energy level?
C. How many electrons fit in the part of the third energy level shown?
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.
What are the energy levels?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
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PLEASE HELP, dana wants...
Answer:
C
Explanation:
Answer:
I think A, not sure
Explanation:
her weight depends on the force of gravity
If half of a radioactive isotope decays in one hour, how much of the original isotope will remain after three hours?
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
what would you observe if sodium and potassium are placed in hot water.
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:
What can you determine about an element if you only know its group number on the periodic table?
A. The total number of protons and neutrons
B. The number of protons
C. The total number of electrons
D. The number of valance elctrons
Answer:
c
Explanation:
Please Help Quick!!!
Lewis Structure of PO3 3-
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
PLEASE HELP ADAP I WILL MARK AS BRAINLYEST
Answer:
c! Hope this helps!
Explanation:
BRAINLIEST PLZ ;)
Answer:
I think its the third one im not sure tho
Explanation:
What is the Law of Conservation of matter, and how does it apply to chemical reactions?
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.
Help!
(Chose all the right answers)
Glucose is made of molecules with the chemical formula seen in the picture
What can we say about glucose molecules?
A) There are 3 different types of atoms in glucose
B) 2 glucose molecules would have 12 C atoms in total
C) Glucose is an element
D) Each glucose has 18 atoms in total
does mitosis begin with a diploid cell?
Answer:
no
Explanation:
Which equation is balanced in an acidic solution?
Answer:
I think C but it could be D
Explanation:
I would say go for C
Lava that cools quickly forms: A. basalt B. granite C.quartz D. none the above
Answer:
I think the answer would be B. hope this helps!!
Explanation:
how many moles of oxygen atoms are in one mole of the molecule Ca5(PO4)3OH? could you also show work
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
The downward movement of water through pores and other spaces in soil due to gravity is called____
A Iniltration
B evaporation
C soakation
D seepage
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.
The ground water recharge is also impacted by this downward motion of water. In areas where the surface of the soil is covered with concrete, infiltration is not possible. Soil water content is due to the movement of water by infiltration.