DUE TOMORROW!!! 15 POINTS
please help!! the answers are already given i just need to show work :( ive been stuck on this for an hour now

Answer:

I NEED TO KNOW THIS TOO

Explanation:

IVE BEEN LOOKING FOR THE ANSWER

Answer:

15.28 mL

Explanation:

From the question given above, the following data were obtained:

Molarity of stock solution (M₁) = 4.5x10¯⁴ M

Volume of diluted solution (V₂) = 275 mL

Molarity of diluted solution (M₂) = 2.5×10¯⁵ M

Volume of stock solution (V₁) needed =.?

The volume of the stock solution needed can be obtained by using the dilution formula as illustrated below:

M₁V₁ = M₂V₂

4.5x10¯⁴ × V₁ = 2.5×10¯⁵ × 275

4.5x10¯⁴ × V₁ = 0.006875

Divide both side by 4.5x10¯⁴

V₁ = 0.006875 / 4.5x10¯⁴

V₁ = 15.28 mL

Therefore, the volume of the stock solution needed is 15.28 mL

Answer:

B

Explanation:

I hope its right. I'm pretty sure.

Answer:

Explanation:

Copper Atom

Answer:

Molecular formula = C₄H₁₂O₂

Explanation:

Given data:

Percentage of hydrogen = 13.80%

Percentage of carbon = 51.02%

Percentage of oxygen = 35.18%

Molecular formula = ?

Solution:

Number of gram atoms of H = 13.80 / 1.01 = 13.6

Number of gram atoms of O = 35.18 / 16 = 2.2

Number of gram atoms of C = 51.02 / 12 = 4.25

Atomic ratio:

            C                      :      H             :         O

           4.25/2.2           :     13.6/2.2     :       2.2/2.2

            2                      :        6          :        1

C : H : O = 2 : 6 : 1

Empirical formula is C₂H₆O.

Molecular formula:

Molecular formula = n (empirical formula)

n = molar mass of compound / empirical formula mass

Empirical formula mass = C₂H₆O = 46 g/mol

n = 88 / 46

n = 2

Molecular formula = n (empirical formula)

Molecular formula = 2 (C₂H₆O)

Molecular formula = C₄H₁₂O₂

Answer:

A student is drinking a cup of hot chocolate as they sit by a campfire on a chilly evening. They know that the cup of hot chocolate transfers thermal energy to the surrounding air. The heated air over their cup of hot chocolate expands and rises and is replaced by cooler, denser air.

This method of energy transfer is

Explanation:

Answer:

radiation

Explanation:

radiation is when an existing heat source spreads heat to its surroundings

Answer:

NaCl (Na is a metal and Cl is a nonmetal) MgO (Mg is a metal and O is a nonmetal) Al2O3, NaF, Na2O

Explanation:

You have to have a metal and a non metal together for it to be ionic

Elements which composed of an equal amount of three components protons, neutrons and electrons are considered neutral elements. example of neutral elements are hydrogen, helium, lithium and beryllium...

by rounding them to the neerest 10

Answer:

5446.8 J

Explanation:

From the question given above, the following data were obtained:

Mass (M) = 50 g

Initial temperature (T₁) = 70 °C

Final temperature (T₂) = 192.4 °C

Specific heat capacity (C) = 0.89 J/gºC

Heat (Q) required =?

Next, we shall determine the change in the temperature. This can be obtained as follow:

Initial temperature (T₁) = 70 °C

Final temperature (T₂) = 192.4 °C

Change in temperature (ΔT) =?

ΔT = T₂ – T₁

ΔT = 192.4 – 70

ΔT = 122.4 °C

Finally, we shall determine the heat required to heat up the block of aluminum as follow:

Mass (M) = 50 g

Specific heat capacity (C) = 0.89 J/gºC

Change in temperature (ΔT) = 122.4 °C

Heat (Q) required =?

Q = MCΔT

Q = 50 × 0.89 × 122.4

Q = 5446.8 J

Thus, the heat required to heat up the block of aluminum is 5446.8 J

Answer:

Ca2+

Explanation:

Answer:

1.The law does not hold true if the different isotopes of the element are involved in making chemical compound.

2.The law is not applicable when elements combine in the same ratio but different compounds are formed.

Answer: energy is transferred, but it can go to the products or the reactants.

Explanation: in a chemical reaction, the atoms and molecules that interact with each other are called reactants.

Answer:

Explanation:

They are the molecules that are formed when four atoms chemically bond together.

Explanation:

tala it is also called myopia lekhnu hai

Äni Arko MA it is also called hypermetropia .

Answer:

Atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. A chemical bond is a force of attraction between atoms or ions

Explanation:

Which statement about photosynthesis is FALSE?

Answer:

b. Oxygen is needed as a reactant to produce

glucose is the incorrect statement here

Explanation:

plants uses simple raw materials to prepare their food , which includes water ( H2O ) and Carbon dioxide ( CO2 ).

and traps sunlight by Green pigments known as chlorophyll and stores these energy in bonds of glucose molecules

so ,

after this reaction glucose and oxygen is formed as products

● hence we conclude that Oxygen is not needed as a reactant to produce glucose , oxygen is the bi product formed during photosynthesis.

Answer:

C. Daily Organizer. Also called an agenda. We usually write notes in them for school related things so the answer is pretty self explanatory.

Answer:

its due to the solvents being factored. to be prepared for the solution you would need a chemical change as the solvents get factored so this will mean that it will have a chemical reaction. in this case its slightly different so it will be called a chemical change as 2 different chemicals change and evolve.

Explanation:

Answer:

0.807 moles

Explanation:

No of molecules = No of mole × Avogadro's number

No of mole = No of molecules / Avogadro's number

No of mole = 5.24×10^23/6.02×10^23

0.870 moles

Answer:

rest until and unless an external force is applied.

Answer:

Oh thats great..

But I hate juice :(

Answer:

ocean

Explanation:

because its easy

Answer:

116 years

Explanation:

To solve this, we will use the half life equation;

A(t) = A_o(½)^(t/t_½)

Where;

A(t) is the amount of strontium left after t years;

A_o is the initial quantity of strontium that will undergo decay;

t_½ is the half-life of strontium

t is the time it will take to decay

We are given;

A(t) = 7.5 g

A_o = 120 g

From online values, half life of strontium-90 is 29 years. Thus, t_½ = 29

Thus;

7.5 = 120 × ½^(t/29)

Divide both sides by 120 to get;

7.5/120 = ½^(t/29)

0.0625 = ½^(t/29)

In 0.0625 = (t/29) In ½

-2.772589 = (t/29) × (-0.693147)

(t/29) = -2.772589/(-0.693147)

t/29 = 4

t = 29 × 4

t = 116 years

Answer:

Beautiftul, begging under F

honest, beginning in thrid line under A

hopeful, fifth line under F

Explanation:

Answer:

you will get 17.983 g of lithium for every 100 g of lithium phosphate.

Explanation:

69.7%  is the percent by mass of Lithium in  Li[tex]_3[/tex]PO[tex]_3[/tex]. A percent is obtained by multiplying the result by 100.

One approach to show the concentration for an element within a compound or component in a combination is as a mass percentage. The mass percentage is computed by dividing the total weight of the combination by the mass of each component and multiplying the result by 100%. The mass percent is calculated by dividing the mass that contains the compound and solute by the mass for the element or solute.

99.795g/mol = molar mass of  Li[tex]_3[/tex]PO[tex]_3[/tex]

6.94g/mol = molar mass of Li

mass percentage of Li=(molar mass of Li/molar mass of Li[tex]_3[/tex]PO[tex]_3[/tex])×  100

=(6.94/99.7)×  100

=69.7%

To know more about mass percentage, here:

brainly.com/question/32197511

#SPJ6

Answer:

Stronger

And its science

Explanation:

Answer:

stronger for top.

weaker for bottom.

passed all sciences in freshman year :D

Doing this because I know I'm kickass at Chemistry.

One source would be human emissions. As humans, we use a lot of machines (like power plants) that produce large amounts of carbon dioxide into the atmosphere. The ocean also produces a lot of carbon dioxide via the evaporation cycle. Polluted waters eventually will go into the atmosphere. Volcanoes, even when not erupted, emit a lot of carbon dioxide as well. Dormant underground magma releases carbon dioxide through the Earth's pores, and even when a volcano erupts, it produces carbon dioxide as well.