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dexar [7]
2 years ago
15

The runners have just started a race. They started at rest and are getting faster.

Chemistry
1 answer:
Anon25 [30]2 years ago
7 0

A.  Acceleration is positive and speed is increasing.

<h3>Further explanation</h3>

The motion performed by a runner is part of a uniformly accelerated motion with constant acceleration.

Equation used  

\tt \boxed{\bold{v_f=v_i+at}}  

vf = final velocity  

vi = vo = initial velocity  

When a runner moves from rest, his speed will increase from being at rest (vi=0) and then move with a constant acceleration(a), and as soon as he crosses the finish line his acceleration will decrease (experience a deceleration ⇒a=- ) and decrease his speed until it finally stops

Velocity and speed are different because velocity itself is a vector quantity that takes into account direction and displacement, while speed is a scalar quantity (only distance).

So the speed does not take positive or negative values because it involves direction, while acceleration takes positive and negative values (deceleration) because it takes direction.

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What is the balanced NET ionic equation for the reaction when aqueous Cs₃PO₄ and aqueous AgNO₃ are mixed in solution to form sol
rusak2 [61]

Answer:

PO_4^{3-}(aq)+3Ag^+(aq)\rightarrow Ag_3PO_4(s)

Explanation:

Hello!

In this case, since the net ionic equation of a chemical reaction shows up the ionic species that result from the simplification of the spectator ions, which are those at both reactants and products sides, we take into account that aqueous species ionize into ions whereas liquid, solid and gas species remain unionized. In such a way, for the reaction of cesium phosphate and silver nitrate we can write the complete molecular equation:

Cs_3PO_4(aq)+3AgNO_3(aq)\rightarrow Ag_3PO_4(s)+3CsNO_3(aq)

Whereas the three aqueous salts are ionized in order to write the following complete ionic equation:

3Cs^+(aq)+PO_4^{3-}(aq)+3Ag^+(aq)+3NO_3^-(aq)\rightarrow Ag_3PO_4(s)+3Cs^+(aq)+3NO_3^-(aq)

In such a way, since the cesium and nitrate ions are the spectator ions because of the aforementioned, the net ionic equation turns out:

PO_4^{3-}(aq)+3Ag^+(aq)\rightarrow Ag_3PO_4(s)

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7 0
2 years ago
Electrical energy is the energy of__________
Arturiano [62]

Answer:

<h3>electrical energy is the energy of Kinetic energy </h3>

Explanation:

<h3>I hope l helped you.</h3>
6 0
2 years ago
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formic acid buffer containing 0.50 M HCOOH and 0.50 M HCOONa has a pH of 3.77. What will the pH be after 0.010 mol of NaOH has b
HACTEHA [7]

Answer:

pH = 3.95

Explanation:

It is possible to calculate the pH of a buffer using H-H equation.

pH = pka + log₁₀ [HCOONa] / [HCOOH]

If concentration of [HCOONa] = [HCOOH] = 0.50M and pH = 3.77:

3.77 = pka + log₁₀ [0.50] / [0.50]

<em>3.77 = pka</em>

<em />

Knowing pKa, the NaOH reacts with HCOOH, thus:

HCOOH + NaOH → HCOONa + H₂O

That means the NaOH you add reacts with HCOOH producing more HCOONa.

Initial moles of 100.0mL = 0.1000L:

[HCOOH] = (0.50mol / L) ₓ 0.1000L = 0.0500moles HCOOH

[HCOONa] = (0.50mol / L) ₓ 0.1000L = 0.0500moles HCOONa

After the reaction, moles of each species is:

0.0500moles HCOOH - 0.010 moles NaOH (Moles added of NaOH) = 0.0400 moles HCOOH

0.0500moles HCOONa + 0.010 moles NaOH (Moles added of NaOH) = 0.0600 moles HCOONa

With these moles of the buffer, you can calculate pH:

pH = 3.77 + log₁₀ [0.0600] / [0.0400]

<h3>pH = 3.95</h3>

3 0
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Where is the majority of Earth’s water found?<br><br> glaciers
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