A student performed an experiment to test the acidity of foods. Put the following steps in the order they should occur.

The indicator used in this redox titration is sulfuric acid

anygoal [31]

Methyle orange is the indicator that is used in sulfuric acid.

4 0

3 years ago

Find [H+] of a 0.056 M hydrofluoric acid solution. Ka = 1.45 x 10-7

brilliants [131]

Answer: $[H^+]$ of 0.056 M HF solution is $8.96\times 10^{-5}$

Explanation:

$HF\rightarrow H^+F^-$

cM 0 0

$c-c\alpha$ $c\alpha$ $c\alpha$

So dissociation constant will be:

$K_a=\frac{(c\alpha)^{2}}{c-c\alpha}$

Give c= 0.056 M and $\alpha$ = ?

$K_a=1.45\times 10^{-7}$

Putting in the values we get:

$1.45\times 10^{-7}=\frac{(0.056\times \alpha)^2}{(0.056-0.056\times \alpha)}$

$(\alpha)=0.0016$

$[H^+]=c\times \alpha$

$[H^+]=0.056\times 0.0016=8.96\times 10^{-5}$

Thus $[H^+]$ of 0.056 M HF solution is $8.96\times 10^{-5}$

8 0

3 years ago

Under the right conditions aluminum will react with chlorine to produce aluminum chloride.

salantis [7]

Answer:

$m_{Al}=9.42gAl$

Explanation:

Hello there!

In this case, according to the given chemical reaction:

2 Al + 3 Cl2 --> 2 AlCl3

Whereas there is a 2:3 mole ratio of aluminum to chlorine; it will be possible for us to calculate the required grams of aluminum by using the equality 22.4 L = 1 mol, the aforementioned mole ratio and the atomic mass of aluminum (27.0 g/mol) to obtain:

$m_{Al}=11.727LCl_2*\frac{1molCl_2}{22.4LCl_2}*\frac{2molAl}{3molCl_2} *\frac{27.0gAl}{1molAl} \\\\m_{Al}=9.42gAl$

Regards!

8 0

3 years ago

Can you guys give some science fair project ideas(8th grade)

Anton [14]

Answer
i’m in 7th grade but for this years science fair i did, “ how does temperature affect the elasticity of rubber bands”

Guide a growing plant through a maze.
8th Grade Science Plant Maze KiwiCo

Prove that plants really do seek out the light by setting up a simple or complex maze. This is a simple 8th grade science project with really cool results.

Blow out a candle with a balloon.

Blowing up a balloon with baking soda and vinegar is the classic acids and bases experiment. Take it a step further by experimenting with the carbon dioxide it produces. (Don’t be afraid of fire in the science

Stand on a pile of paper cups.

Combine physics and engineering and challenge 8th grade science students to create a paper cup structure that can support their weight. This is a cool project for aspiring architects.

hope this helps and have a wonderful day :)

5 0

3 years ago

Gaseous vapor observed when handling dry ice (solid co_2 2 ) physical or chemical

Nadya [2.5K]

<span>Dry ice is frozen carbon dioxide. It is easy to assume that the fog surrounds dry ice is carbon dioxide returning to it's gaseous however, you can not see that process. The vapors you see is the water molecules in the air condensing as a result of the cooling or energy removal by the dry ice. When energy is removed from water molecules they become colder and move slower than water in a gaseous. Similar to clouds in the air, the water condenses into a form that you can see.</span>

3 0

3 years ago