Kinetic friction is the frictional force needed to start an object at rest into

Examine the unbalanced electrolytic reaction.

romanna [79]

<span>2Li⁺(aq) + Zn⁰(s) → 2Li⁰(s) + Zn²⁺(aq)

</span>2Li⁺(aq) + 2e⁻ → 2Li⁰(s)
Zn⁰(s) → Zn²⁺(aq) +2e⁻

2 electrons are transferred from atom of Zn⁰ to 2 ions of Li⁺.

3 0

3 years ago

What pressure is required to achieve a co2 concentration of 7.90×10−2 m at 20∘c?

Savatey [412]

Answer:- 1.90 atm

Solution:- It is based on combined gas law equation, PV = nRT

In this equation, P is pressure, V is volume, n is moles of gas, R is universal gas constant and T is kelvin temperature.

If we divide both sides by V then:

$P=\frac{nRT}{V}$

We know that, molarity is moles per liter. So, in the above equation we could replace $\frac{n}{V}$ by molarity, M of the gas. The equation becomes:

P = MRT

T = 20 + 273 = 293 K

M = $7.9*10^-^2$

Let's plug in the values in the equation:

P = $(7.9*10^-^2)(0.0821)(293)$

P = 1.90 atm

So, the pressure of the gas is 1.90 atm.

7 0

3 years ago

32. Barium sulfate, BaSO4, is a white crystalline solid that is insoluble in water. It is used by doctors to diagnose

DIA [1.3K]

Answer:

42

Explanation:

bygyytrdesf

7 0

2 years ago

A student heats a sample of hydrate once, and the mass of the sample and the evaporating dish is 16.428 g. After a second heatin

jolli1 [7]

Answer:

12.371 g

Explanation:

Given :

$m_{evaporating\ dish}=1.135\ g$

$m_{evaporating\ dish}+m_{Hydrate\ sample}=25.637\ g$

$m_{evaporating\ dish}+m_{First\ heated\ sample}=16.428\ g$

$m_{evaporating\ dish}+m_{Second\ heated\ sample}=13.266\ g$

Mass of salt hydrate:

$m_{evaporating\ dish}=1.135\ g$

$m_{evaporating\ dish}+m_{Hydrate\ sample}=25.637\ g$

$m_{Hydrate\ sample}=25.637-m_{evaporating\ dish}\ g=25.637-1.135\ g=24.502\ g$

Mass of salt anhydrous:

$m_{evaporating\ dish}=1.135\ g$

$m_{evaporating\ dish}+m_{Second\ heated\ sample}=13.266\ g$

$m_{Second\ heated\ sample}=m_{salt\ anhydrous}=13.266-m_{evaporating\ dish}\ g=13.266-1.135\ g=12.131\ g$

Mass of water:

$m_{water}=m_{Hydrate\ sample}-m_{salt\ anhydrous}=24.502-12.131\ g=12.371\ g$

$m_{water}=12.371\ g$

4 0

3 years ago

These models show the electron structures of two different nonmetal elements.

Soloha48 [4]

Answer: Option (D) is the correct answer.

Explanation:

Valence shell is the shell present on the outermost core of an atom and electrons present in the valence shell are known as valence electrons.

If an atom has completely filled valence shell then it means the atom is not reactive in nature because it is already stable.

But when an atom has less than eight electrons in its valence shell then it means to attain stability the atom will readily attract electrons towards itself.

As the given element 1 has 8 electrons in its valence shell. Hence, it is not reactive in nature but element 2 has 6 valence electrons. So, in order to attain stability element 2 will readily attract 2 electrons from a donor atom.

Thus, we can conclude that element 2 is more reactive because it does not have a full valence shell, so it will attract electrons.

4 0

3 years ago