The value of a scientific variable:

In the diagram to the right, the battery provides 12 V to the circuit made up of three identical light bulbs. When the switch is

chubhunter [2.5K]

I don’t know I need that answer to

3 0

3 years ago

What is the molarity of 70.6 g C2H6O in 2.25 L of solution

myrzilka [38]

Hey there!

Molar mass C2H6O = 46.0684 g/mol

Number of moles:

n = mass of solute / molar mass

n = 70.6 / 46.0684

n = 1.532 moles

Therefore:

M = number of moles / volume ( L )

M = 1.532 / 2.25

= 0.680 M

Hope that helps!

7 0

4 years ago

Calculate the weight percent of ascorbic acid in a tablet of Vitamin C from the following data:A 80 mg sample of a crushed Vitam

Lina20 [59]

Answer:

The Answer is 88%

Explanation:

The balanced ionic equation of the reaction

$IO^{3- }+ 8 I^- + 6 H^+ => 3 I^{3- }+ 3 H_2O$

$I^{3-} + 2 S_2O_3^{2-} => 3 I^- + S_4O_6^{2-}$

$C_6H_8O_6 + I^{3- }+ H_2O => C_6H_6O_6 + 3 I^- + 2 H^+$

Looking at the above reactions

The original number of moles of $I^{3-}$ = 3 × number of moles of $IO^{3-}$

= 3 × volume × concentration of $KIO_3$

Note: The formula for number of moles is volume × concentration

$=3 * \frac{40}{1000} * 0.00653 =0.000784$ mol

The number of moles of $I^{3-}$ left after its reaction with ascorbic acid

= $\frac{1}{2}$ x moles of $S_2O_3^{2-}$

= $\frac{1}{2}$ x volume x concentration of $S_2O_3^{2-}$

$= \frac{1}{2} * \frac{15}{1000} * 0.0510 =0.000383 \ mol$

Note: The division by 1000 is to convert mill liter to liter

Moles of ascorbic acid = moles of $I^{3-}$ reacted

$= initial \ moles \ of \ I^{3-} \ - remaining \ moles \ of \ I^{3-}$

$=0.000784 - 0.000383$

$=0.000401 \ mols$

$Mass = moles \ * molar \ mass$

Hence

Mass of ascorbic acid = moles of ascorbic acid × molar mass of ascorbic acid

$= 0.000401* 176.12 = 0.07055\ g$

$= 70.55\ mg$

Weight% of ascorbic acid = mass of ascorbic acid/mass of sample x 100%

= 70.55/80 × 100%

= 88.1%

3 0

4 years ago

Which of the following describes metallic character on the periodic table?

IceJOKER [234]

Answer:

<em>C. It increases as you move left to right within a period and up a group on the periodic table.</em>

7 0

3 years ago

What describes how computer programs convert design sketches into three dimensional images

weeeeeb [17]

Answer:

The programs take two-dimensional images and allow the user to manipulate cubes and prisms to create their design sketches.

Explanation:

Instead of working with squares and triangles, the programs allow the users to manipulate cubes and prisms to create their design sketches. Additionally, the programs can take two-dimensional pictures and convert them to possible three-dimensional images.

I got you bro :)

Sorry he took your points :(

- massmaster34

4 0

3 years ago