All categories

2 years ago

determine if the pennies are made of pure copper by comparing the density with that of the pure copper

Chemistry

1 answer:

zhenek [66]2 years ago

4 0

Answer:

The pennies are NOT made of pure copper since the obtained density is 9.29 g/cm3 which is greater than the density of copper which is 8.96 g/cm3.

Explanation:

You might be interested in

ASAP! WILL GIVE BRAINIEST

Genrish500 [490]

Create and use more electricity then previously used before. A lot of power is created by burning fossil fuels, the burning of them will be increased so more is needed to give power to everyone.

8 0

3 years ago

When products are being made as quickly as reactants, the reaction is said to have reached... what?

Tema [17]

Answer: Equilibrium

Explanation:

The reactions which do not go on completion and in which the reactant forms product and the products goes back to the reactants simultaneously are known as equilibrium reactions.

For a chemical equilibrium reaction, equilibrium state is achieved when the rate of forward reaction becomes equals to rate of the backward reaction which means the products are being made as quickly as reactants

Equilibrium state is the state when reactants and products are present but the concentrations does not change with time.

4 0

3 years ago

Semasa proses pengewapan, cecair bertukar menjadi gas. Apakah yang berlaku kepada zarah dalam cecair??

katovenus [111]

Can you translate in english i can’t understand this

4 0

3 years ago

The intersection angle of a 3 degree curve is 45.2 degrees. What is the length of the curve? of Select one: O a. 455 m O b.573 m

ValentinkaMS [17]

Explanation:

Relation between length of a curve and angle is as follows.

l = $R \times \Theta$

where, R = radius of curve

$\Theta$ = angle in radians

Also, l = $R \times \Theta \times \frac{\pi}{180}$ .......... (1)

If curve has a degree of curvature $D_{a}$ for standard length s, then

R = $\frac{s}{D_{a}} \times \frac{180}{\pi}$ ........... (2)

Now, substitute the value of R from equation (2) into equation (1) as follows.

l = $\frac{s \times \Theta}{D_{a}}$

If s = 30 m, then calculate the value of l as follows.

l = $\frac{s \times \Theta}{D_{a}}$

= $30 \times \frac{45.2}{3}$

= 452 m

thus, we can conclude that the length of the curve is 452 m.

7 0

3 years ago

Which reactions are oxidation-reduction reactions? check all that apply. fes(s) 2hcl(aq) â†’ h2s(g) fecl2(g) agno3(aq) nacl(aq)

Dafna1 [17]

oxidation-reduction reactions are -

2C3H6(g) + 9O2(g) → 6CO2(g) + 6H2O(g)
Fe2O3(s) + 3CO(g) → 2Fe(l) + 3CO2(g)

For reaction,

2C3H6(g) + 9O2(g) → 6CO2(g) + 6H2O(g)

On reactant side:

Oxidation state of Carbon = +2

Oxidation state of Oxygen = 0

On product side:

Oxidation state of Carbon = +4

Oxidation state of Oxygen = -2

Here, carbon's oxidation state is rising from +2 to +4. As a result, it is oxidizing and the oxygen's oxidation state is decreasing from 0 to -2. As a result, it is decreasing.

For reaction,

Fe2O3(s) + 3CO(g) → 2Fe(l) + 3CO2(g)

When reacting:

Iron's oxidation state is +3.

Carbon's oxidation state is +2.

On product side:

Iron's oxidation state is zero.

Carbon's oxidation state is +4.

Here, carbon's oxidation state is rising from +2 to +4. As a result, it is being oxidized and the iron's oxidation state is changing from +3 to 0. As a result, it is decreasing.

To learn more about oxidation-reduction from given link

brainly.com/question/5794822

#SPJ4

7 0

2 years ago