All categories

3 years ago

Chlorine atoms tend to form ions by taking in one electron. This means the atom has

Chemistry

1 answer:

8090 [49]3 years ago

8 0

Answer:

The additional electron does not affect the atomic number nor the mass number. The atomic mass is the sum of neutrons and protons. Electrons are not accounted in atomic mass as their mass is so small, approximately 1/1,836 of a protons mass. Atomic number is the total number of protons of an atom. Chlorine taking in another electron will not change its atomic number. In an ion, the atomic number and atomic mass do not change from the original.

You might be interested in

Why does mantle rock begin to sink back towards the lower mantle from the area closest to the crust?

Delvig [45]

Answer: Convection Currents

Explanation: The mantle rock is solid and denser because it is cooler. This means it will sink closer to lower mantle as warmer, lense dense rock/magma moves upwards.

8 0

3 years ago

The Sun is a yellow star that's both average in brightness and temperature and is classified as

Roman55 [17]

Answer:

Classifying stars according to their spectrum is a very powerful way to begin to understand how they work. As we said last time, the spectral sequence O, B, A, F, G, K, M is a temperature sequence, with the hottest stars being of type O (surface temperatures 30,000-40,000 K), and the coolest stars being of type M (surface temperatures around 3,000 K). Because hot stars are blue, and cool stars are red, the temperature sequence is also a color sequence. It is sometimes helpful, though, to classify objects according to two different properties. Let's say we try to classify stars according to their apparent brightness, also. We could make a plot with color on one axis, and apparent brightness on the other axis, like this:

Explanation:

7 0

3 years ago

Stearic acid (C18H36O2) is a fatty acid, a molecule with a long hydrocarbon chain and an organic acid group (COOH) at the end. I

Paha777 [63]

Answer:

There is 9671 Kj of heat released

Explanation:

Step 1: The balanced equation:

C18H36O2(s) + 26O2(g) --> 18CO2(g)+18H2O(g)

This means for 1 mole of C18H36O2 consumed there is 26 moles of O2 needed to produce 18 moles of CO2 and 18 moles of H2O.

Step 2: Calculate the heat of combustion

ΔH (combustion) = [18*(ΔHf of CO2) + 18*(ΔHf of H2O)] - [1*(ΔHf of C18H36O2) + 26*(ΔHf of O2)]

ΔH (combustion) = [18*(-394 kJ/mol) + 18*(-242 kJ/mol)] - [1*(-948 kJ/mol) + 26*(0 kJ/mol)]

ΔH (combustion) = [(-7092 kJ/mol) + (-4356 kJ/mol)] - (-948 kJ/mol)

= -10500 kJ/mol

ΔH (combustion) = heat released / number of moles of stearic acid

Step 3: Calculate moles of stearic acid

moles of stearic acid = mass / Molar mass of stearic acid

moles of stearic acid = 262g / 284.48 g/mole = 0.921 moles

Step 4: Calculate moles of oxygen

moles of O2 = 914.5 / 32g/mole

moles of O2 = 28.578125 moles

Stearic acid is the limiting reactant: it will completely react

There will react 26*0.921 mole = 23.946 mole of O2

This means there will remain 4.63 moles of O2

Step 5: Calculate heat released

q = (ΔH combustion) * (moles of stearic acid) = (-10500 kJ/mol) * (0.921 moles) = 9671 Kj

There is 9671 Kj of heat released

6 0

3 years ago

Write the Henderson-Hasselbalch equation for a propanoic acid solution ( CH3CH2CO2H , pKa=4.874 ) using the symbols HA and A− ,

zysi [14]

Answer:

a) [A⁻]/[HA] = 0.227

b) [A⁻]/[HA] = 0.991

c) [A⁻]/[HA] = 2.667

Explanation:

In the Henderson-Hasselbalch equation, HA stands from an acid an A⁻ stands from its conjugate base, as follows:

CH₃CH₂CO₂H = HA

CH₃CH₂CO₂⁻ = A⁻

pH = pka + Log [A⁻]/[HA]

pH = 4.874 + Log[CH₃CH₂CO₂⁻]/[CH₃CH₂CO₂H]

(a)

4.23 = 4.874 + Log [A⁻]/[HA]

-0.644 = Log [A⁻]/[HA]

$10^{-0.644}$ = [A⁻]/[HA]

0.227 = [A⁻]/[HA]

(b)

4.87 = 4.874 + Log [A⁻]/[HA]

-0.004 = Log [A⁻]/[HA]

$10^{-0.004}$ = [A⁻]/[HA]

0.991 = [A⁻]/[HA]

(c)

5.30 = 4.874 + Log [A⁻]/[HA]

0.426 = Log [A⁻]/[HA]

$10^{0.426}$ = [A⁻]/[HA]

2.667 = [A⁻]/[HA]

6 0

4 years ago

According to Newton’s second law of motion, when an object is acted on by an unbalanced force, how will that object respond? It

otez555 [7]

Answer:

C) It will accelerate.

Explanation:

According to Newton’s second law of motion, when an object is acted on by an unbalanced force, it will accelerate.

An unbalanced force will change the speed or direction (or both) of an object. A change in speed and/or direction is acceleration.

A) is wrong. The object will stop moving only if there is a balanced force in the opposite direction.

B) is wrong. The object will decrease speed only if the unbalanced force has a component opposite to the direction of motion.

d) is wrong. The object will increase speed only if the unbalanced force has a component in the direction of motion.

7 0

3 years ago