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3 years ago

Question 4

Chemistry

1 answer:

S_A_V [24]3 years ago

4 0

Answer:

Heat is released.

Explanation:

In an exothermic reaction, the reactant(s) move into a more stable state when they form into the product(s). Thus, the excess energy is released in the form of heat.

Conversely, in an endothermic reaction, the reactant(s) move into a more unstable state. In doing so, energy is required for the chemical reaction to occur to force the reactant(s) into a less stable state. So, energy is absorbed to make the reaction occur.

Also, since energy was released, the net energy decreased. If energy was absorbed in an endothermic reaction, the net energy would increase.

Therefore, the answer is 'Heat is released'.

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In the figure below, two nonpolar molecules are interacting.Which interaction would most likely cause these molecules to repel e

Fed [463]

Two non-polar molecules are most likely to interact by
induced dipole-induced dipole interaction.

Non-polar substances do not have a permanently established charge distribution due to similar electron affinities of the atoms that are present. Moreover, due to the absence of a polar hydrogen, they cannot exhibit hydrogen bonding. They interact with one another by induced dipole-induced dipole interactions which arise from the molecules of the substances coming into close vicinity of one another.

6 0

3 years ago

Read 2 more answers

You are instructed to create 900. mL of a 0.29 M phosphate buffer with a pH of 7.8. You have phosphoric acid and the sodium salt

Aleksandr [31]

Answer:

B and C

Explanation:

When we have to do a buffer solution we always have to choose the reaction that has the pKa closer to the desired pH value. When we find the pKa values we will obtain:

$pKa_1=-Log[6.9x10^-^3]=2.16$

$pKa_2=-Log[6.2x10^-^8]=7.20$

$pKa_3=-Log[4.8x10^-^13]=12.31$

The closer value is pKa2 with a value of 7.2. Therefore we have to use the second reaction. In which $H_2PO_4^-^1$ is the acid and $HPO_4^-^2$ is the base. Therefore the answer for the first question is B and the answer for the second question is C.

8 0

3 years ago

A balloon occupies a volume of 2.00 l at 40.0oc. how much volume will it occupy at 30.0oc?

hodyreva [135]

Charles' law says "at a constant pressure, the volume of a fixed amount of gas is directly proportional to its absolute temperature".

V α T

Where V is the volume and T is the temperature in Kelvin of the gas. We can use this for two situations as,
V₁/T₁ = V₂/T₂

V₁ = 2.00 L
T₁ = 40.0 ⁰C = 313 K
V₂ = ?
T₂ = 30.0 ⁰C = 303 K

By applying the formula,
2.00 L / 313 K = V₂ / 303 K
V₂ = (2.00 L / 313 K) x 303 K
V₂ = 1.94 L

Hence, the volume of the balloon at 30.0 ⁰C is 1.94 L

7 0

4 years ago

A 40.0 L balloon is filled with air at sea level (1 atm @ 25 oC). It is then tied to a rock and thrown into a cold lake and it s

velikii [3]

To solve this question you need to calculate the number of the gas molecule. The calculation would be:
PV=nRT
n=PV/RT
n= 1 atm * 40 L/ (0.082 L atm mol-1K-1 * 298.15K)
n= 1.636 moles

The volume at bottom of the lake would be:
PV=nRT
V= nRT/P
V= (1.636 mol * 277.15K* 0.082 L atm mol-1K-1 )/ 11 atm= 3.38 L

8 0

3 years ago

Which system is not directly connected to itself

Nataliya [291]

Answer:

B) Digestive

Explanation:

The system is dependent in the digestive system because it sends the nutrients to the bones and this helps the bone growth and the repair. It can not be A. since the skeleton system is connected with the muscular system physically, this is to protect muscles and allow the skeletal muscles to make the bones move, so this system is connected with itself with the help of the muscular system! The endocrine is somewhat connected with the nervous system, they are both essential to the communication and response system. This eliminates A and C and leaves you with B!

5 0

3 years ago