How many grams of water can be heated 20C by the addition of 1000J?

An electric current is applied to a 1.0 m nai solution. (i) write the balanced oxidation half reaction for the reaction that tak

MakcuM [25]

Answers are:
1) The balanced oxidation half reaction: 2I⁻(aq) → I₂(s) + 2e⁻.
Iodine is oxidized (lost electrons) from -1 to neutral charge (0).
2) The balanced reduction half-reaction: 2H₂O(l) + 2e⁻ → H₂(g) + 2OH⁻.
Hydrogen is reduced (gain electrons) from +1 to neutral charge.
3) The oxidation <span>reaction takes place at the anode.</span>

5 0

3 years ago

If air contains 78% Nitrogen by volume, what is the solubility of nitrogen in water at 25 degree celisus

Svet_ta [14]

The solubility of nitrogen in water at 25 °C= 4.88 x 10⁻⁴ mol/L

<h3>Further explanation</h3>

Given

78% Nitrogen by volume

Required

The solubility of nitrogen in water

Solution

Henry's Law states that the solubility of a gas is proportional to its partial pressure

Can be formulated

S = kH. P.

S = gas solubility, mol / L

kH = Henry constant, mol / L.atm

P = partial gas pressure

In the standard 25 C state, the air pressure is considered to be 1 atm, so the partial pressure of N₂ -nitrogen becomes:

Vn / Vtot = Pn / Ptot

78/100 = Pn / 1

Pn = 0.78 atm

Henry constant for N₂ at 25 °c = 1600 atm/mol.L=6.25.10⁻⁴ mol/L.atm

The solubility :

$\tt S=6.25.10^{-4}\times 0.78\\\\S=4.88\times 10^{-4}~mol/L$

7 0

2 years ago

A chemical reaction was used to produce 2.95 moles of copper(II) bicarbonate, Cu(HCO3)2.

BARSIC [14]

Answer:

About 547 grams.

Explanation:

We want to determine the mass of copper (II) bicarbonate produced when a reaction produces 2.95 moles of copper (II) bicarbonate.

To do so, we can use the initial value and convert it to grams using the molar mass.

Find the molar mass of copper (II) bicarbonate by summing the molar mass of each individual atom:

$\displaystyle \begin{aligned} \text{MM}_\text{Cu(HCO$_3$)$_2$} &= (63.55 + 2(1.01)+2(12.01)+6(16.00))\text{ g/mol} \\ \\ &=185.59\text{ g/mol} \end{aligned}$

Dimensional Analysis:

$\displaystyle 2.95\text{ mol Cu(HCO$_3$)$_2$}\cdot \frac{185.59 \text{ g Cu(HCO$_3$)$_2$}}{1 \text{ mol Cu(HCO$_3$)$_2$}} \Rightarrow 547 \text{ g Cu(HCO$_3$)$_2$ }$

In conclusion, about 547 grams of copper (II) bicarbonate is produced.

8 0

3 years ago

HELPPP TODAY IS THE LAST DAY OF SCHOOL

Alecsey [184]

Answer:

orbiting closer to the earth's surface.....im pretty sure abt it

4 0

3 years ago

Calculate the frequency of electromagnetic wave with the wave length 344nm ( hint: use dimensional analysis)

Svetlanka [38]

Frequency = speed of light
---------------------------
wavelength

= 3 x 10^8
------------------------
344 x 10^-9

= 8.72 x 10^14 Hz.

Hope this helps!

5 0

2 years ago