Which technology is shown in the photograph?

The atomic mass of an element is equal to the:

Stells [14]

Answer:

number of protons and neutrons

Explanation:

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3 years ago

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A chemist designs a galvanic cell that uses these two half-reactions: half-reaction standard reduction potential (s)(aq)(aq)(l)

miv72 [106K]

Answer:

Reduction (cathode): Cu²⁺(⁺aq) + 2 e⁻ → Cu(s)

Oxidation (anode): Zn(s) → Zn²⁺(⁺aq) + 2 e⁻

Cu²⁺(⁺aq) + Zn(s) → Cu(s) + Zn²⁺(⁺aq)

E°cell = 1.10 V

Explanation:

<em>The half-reactions are missing, but I will propose some to show you the general procedure and then you can apply it to your equations.</em>

<em>Suppose we have the following half-reactions.</em>

<em />

To identify how to make a spontaneous cell, we need to consider the standard reduction potentials (E°red). The half-reaction with the higher E°red will occur as a reduction (in the cathode), whereas the one with the lower E°red will occur as an oxidation (in the anode).

Reduction (cathode): Cu²⁺(⁺aq) + 2 e⁻ → Cu(s) E°red = 0.34 V

Oxidation (anode): Zn(s) → Zn²⁺(⁺aq) + 2 e⁻ E°red = -0.76 V

To get the overall equation we add both half-reactions.

Cu²⁺(⁺aq) + Zn(s) → Cu(s) + Zn²⁺(⁺aq)

The standard cell potential (E°cell) is the difference between the standard reduction potential of the cathode and the standard reduction potential of the anode.

E°cell = E°red, cat - E°red, an

E°cell = 0.34 V - (-0.76 V) = 1.10 V

Since E°cell > 0, the reaction is spontaneous.

5 0

3 years ago

A 475 cm3 sample of gas at standard temperature and pressure is allowed to expand until it occupies a

Andrej [43]

The final temperature : 345 K

<h3> Further explanation </h3>

Given

475 cm³ initial volume

600 cm³ final volume

Required

The final temperature

Solution

At standard temperature and pressure , T = 273 K and 1 atm

Charles's Law :

When the gas pressure is kept constant, the gas volume is proportional to the temperature

V₁/T₁=V₂/T₂

Input the value :

T₂=(V₂T₁)/V₁

T₂=(600 x 273)/475

T₂=345 K

4 0

3 years ago

In an experiment, a 0.5297 g sample of diphenylacetylene (C14H10) is burned completely in a bomb calorimeter. The calorimeter is

V125BC [204]

Answer:

the Molar heat of Combustion of diphenylacetylene $(C_{14}H_{10})$ = $-6.931 *10^3 \ kJ/mol$

Explanation:

Given that:

mass of diphenylacetylene $(C_{14}H_{10})$ = 0.5297 g

Molar Mass of diphenylacetylene $(C_{14}H_{10})$ = 178.21 g/mol

Then number of moles of diphenylacetylene $(C_{14}H_{10})$ = $\frac{mass}{molar \ mass}$

= $\frac{0.5297 \ g }{178.24 \ g/mol}$

= 0.002972 mol

By applying the law of calorimeter;

Heat liberated by 0.002972 mole of diphenylacetylene $(C_{14}H_{10})$ = Heat absorbed by $H_2O$ + Heat absorbed by the calorimeter

Heat liberated by 0.002972 mole of diphenylacetylene $(C_{14}H_{10})$ = msΔT + cΔT

= 1369 g × 4.184 J g⁻¹°C⁻¹ × (26.05 - 22.95)°C + 916.9 J/°C (26.05 - 22.95)°C

= 17756.48 J + 2842.39 J

= 20598.87 J

Heat liberated by 0.002972 mole of diphenylacetylene $(C_{14}H_{10})$ = 20598.87 J

Heat liberated by 1 mole of diphenylacetylene $(C_{14}H_{10})$ will be = $\frac{20598.87 \ J}{0.002972 \ mol}$

= 6930979.139 J/mol

= 6930.98 kJ/mol

Since heat is liberated ; Then, the Molar heat of Combustion of diphenylacetylene $(C_{14}H_{10})$ = $-6.931 *10^3 \ kJ/mol$

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3 years ago

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3. Your company makes 1000 boxes of 500 g baking soda per day.

inessss [21]

500,000 g of baking soda is present in 1000 boxes of 500 g baking soda boxes.

Answer:

Option C.

Explanation:

As 500 g of baking soda is taken in each box of that company. The total weight of baking soda in all the boxes can be determined by adding the weights of each box. This is possible only when the number of boxes is less. But if the number of boxes are large, then we can determine the total weight of baking soda by multiplying the number of boxes with the weight in each box.

So in this case, 1000 boxes are present and in that 500 g of baking soda are present in each box.

So total grams of baking soda will be 1000 * 500 = 5,00,000 g.

Thus, 500,000 g of baking soda is present in 1000 boxes of 500 g baking soda boxes.

5 0

3 years ago