URGENT!!!!!!

Please help me please please

anzhelika [568]

Answer:

d

D

C

D

c

Explanation:

8 0

2 years ago

Hurry please need fast

Nina [5.8K]

I think it might be 2 but I could be mistaken sorry if I am

7 0

2 years ago

Which of the following can cause muscle fatigue ?

dezoksy [38]

Answer:

The correct answer is -all of the above.

Explanation:

Muscle fatigue is a reduced ability in work capacity caused by work itself. It is known that altering oxygen is contracting skeletal muscle affects performance. Reduced O2 supply increases the rate of muscle fatigue.

The lactic acid is accumulated as it forms rapidly but the breaking of the lactic acid is slow down, which causes muscle fatigue. Less ATP and glycogen in muscle results in fatigue as the muscle is not able to generate energy to power contractions and therefore contributes to muscle fatigue.

8 0

2 years ago

Warning signs are sometimes placed on aerosol cans to prevent people from throwing them into a fire. What would be true about th

GarryVolchara [31]

Answer:

The correct option is volume stays constant

Explanation:

When a gas container (in this case an aerosol can) is subjected to heat (from fire), the temperature of the can and subsequently the temperature of the gas itself increases, an increase in the temperature of the gas cause the pressure to also increase; as the gas molecules will collide more and faster with each other and against the wall of the can. However, the volume of the gas will remain the same as before it was subjected to the heat - the gas particles do not get destroyed or increased as a result of the heat (law of conservation of matter explains this).

3 0

2 years ago

Read 2 more answers

Glycolic acid, which is a monoprotic acid and a constituent in sugar cane, has a pKa of 3.9. A 25.0 mL solution of glycolic acid

Phoenix [80]

Answer:

pH = 8.0

Explanation:

First, we have to calculate the moles of NaOH.

$35.8 \times 10^{-3}L.\frac{0.020mol}{L} =7.2\times 10^{-4}mol$

Let's consider the balanced equation.

C₂H₄O₃ + NaOH ⇒ C₂H₃O₃Na + H₂O

The molar ratio C₂H₄O₃: NaOH: C₂H₃O₃Na is 1: 1: 1. So, when 7.2 × 10⁻⁴ moles of NaOH react completely with 7.2 × 10⁻⁴ moles of C₂H₄O₃ they form 7.2 × 10⁻⁴ moles of C₂H₃O₃Na.

The concentration of C₂H₃O₃Na is:

$\frac{7.2\times 10^{-4}mol}{60.8 \times 10^{-3}L} =0.012M$

C₂H₃O₃Na dissociates according to the following equation:

C₂H₃O₃Na(aq) ⇒ C₂H₃O₃⁻(aq) + Na⁺(aq)

C₂H₃O₃⁻ comes from a weak acid so it undergoes basic hydrolisis.

C₂H₃O₃⁻ + H₂O ⇄ C₂H₄O₃ + OH⁻

If we know that pKa for C₂H₄O₃ is 3.9, we can calculate pKb for C₂H₃O₃⁻ using the following expression:

pKa + pKb = 14

pKb = 14 -3.9 = 10.1

10.1 = -log Kb

Kb = 7.9 × 10⁻¹¹

We can calculate [OH⁻] using the following expression:

[OH⁻] = √(Kb.Cb) where Cb is the initial concentration of the base

[OH⁻] = √(7.9 × 10⁻¹¹ × 0.012M) = 9.7 × 10⁻⁷ M

Now, we can calculate pOH and pH.

pOH = -log [OH⁻] = -log (9.7 × 10⁻⁷) = 6.0

pH + pOH = 14

pH = 14 - pOH = 14 - 6.0 = 8.0

7 0

2 years ago