All categories

2 years ago

PLEASE HELP ME ANSWER THIS ASAP! !

Chemistry

2 answers:

lara31 [8.8K]2 years ago

8 0

Answer:

Change in velocity is -4m\s

acceleration is -2m\s^2 cause Change in velocity = final v - initial v

Explanation:

Calculating acceleration involves dividing velocity by time — or in terms of SI units, dividing the meter per second [m/s] by the second [s]. Thus the SI unit of acceleration is the meter per second squared .

joja [24]2 years ago

5 0

-4 m/s and -2 m/s2

:-)

You might be interested in

I need the 3 questions !!! About Rubidium (Rb) <br><br> ASAP PLEASE DUE IN LIKE 20 min

hjlf

Answer:

419kJ/mol
5,0,0,+12
That catches fire spontaneously

Explanation:

1. Topic: Chemistry

ElementFirst Ionization Energy (kJ/mol) Lithium520Sodium496Rubidium403Cesium376According to the above table, which is most likely to be the first ionization energy for potassium?

536kJ/mol

504kJ/mol

419kJ/mol

391kJ/mol

358kJ/mol

2. Topic: Chemistry, Atom

The correct set of four quantum numbers for the valence electrons of the rubidium atom (Z=37) is:

5,1,1,+12

5,0,1,+12

5,0,0,+12

5,1,0,+12

3. Rubidium and cesium are pyrophoric. Here the term pyrophoric means:

That hardly catches fire

That does not catch fire at all

That catches fire spontaneously

None of these

5 0

3 years ago

8. Which of the following is TRUE about limiting and excess reactants?

Ivahew [28]

B. The limiting reactant determines the max amount of product that can be formed

5 0

2 years ago

What is the mole ratio of NH3 to N2?

Ksenya-84 [330]

To answer this question a balanced chemical equation is necessary. The correct equation is: N2 + 3H2 = 2NH3
From this equation, one mole of nitrogen react with 3 moles of hydrogen to give 2 moles of ammonia.
Therefore, the mole ratio of NH3 to N2 is 2:1

8 0

2 years ago

What volume of 0.307 m naoh must be added to 200.0ml of 0.425m acetic acid (ka = 1.75 x 10-5 ) to produce a buffer of ph = 4.250

Blababa [14]

The buffer solution target has a pH value smaller than that of pKw (i.e., pH < 7.) The solution is therefore acidic. It contains significantly more protons $\text{H}^{+}$ than hydroxide ions $\text{OH}^{-}$ . The equilibrium equation shall thus contain protons rather than a combination of water and hydroxide ions as the reacting species.

Assuming that $x \; \text{L}$ of the 0.307 $\text{mol} \cdot \text{dm}^{-3}$ sodium hydroxide solution was added to the acetic acid. Based on previous reasoning, $x$ is sufficiently small that acetic acid was in excess, and no hydroxide ion has yet been produced in the solution. The solution would thus contain $0.2000 \times 0.425 - 0.307 \; x = 0.085 - 0.307 \; x$ moles of acetic acid and $0.307 \; x$ moles of acetate ions.

Let $\text{HAc}$ denotes an acetic acid molecule and $\text{Ac}^{-}$ denotes an acetate ion. The RICE table below resembles the hydrolysis equilibrium going on within the buffer solution.

$\begin{array}{lccccc}\text{R} & \text{HAc} & \leftrightharpoons & \text{H}^{+} & + & \text{Ac}^{-}\\\text{I} & 0.085 - 0.307 \; x& & 0 & & 0.307 \; x\\\end{array}$

The buffer shall have a pH of 4.250, meaning that it shall have an equilibrium proton concentration of $10^{4.250}\; \text{mol}\cdot \text{dm}^{-3}$ . There were no proton in the buffer solution before the hydrolysis of acetic acid. Therefore the table shall have an increase of $10^{-4.250}\;\text{mol}\cdot \text{dm}^{-3}$ in proton concentration in the third row. Atoms conserve. Thus the concentration increase of protons by $10^{-4.250}\;\text{mol}\cdot \text{dm}^{-3}$ would correspond to a decrease in acetic acid concentration and an increase in acetate ion concentration by the same amount. That is:

$\begin{array}{lcccccc}\text{R} & \text{HAc} & \leftrightharpoons & \text{H}^{+} & + & \text{Ac}^{-}\\\text{I} & 0.085 - 0.307 \; x& & 0 & & 0.307 \; x\\\text{C} & - 10^{-4.250} & & +10^{-4.250} & & +10^{-4.250} \\\text{E} & 0.085 - 10^{-4.250} - 0.307 \; x& & 10^{-4.250} & & 10^{-4.250} + 0.307 \; x\end{array}$

By definition:

$\text{K}_{a} = [\text{H}^{+}] \cdot [\text{Ac}^{-}] / [\text{HAc}]\\\phantom{\text{K}_{a}} = 10^{-4.250} \times (10^{-4.250} + 0.307 \; x) / (0.085 - 10^{-4.250} - 0.307 \; x)$

The question states that

$\text{K}_{a} = 1.75 \times 10^{-5}$

such that

$10^{-4.250} \times (10^{-4.250} + 0.307 \; x) / (0.085 - 10^{-4.250} - 0.307 \; x) = 1.75 \times 10^{-5}\\6.16 \times 10^{-5} \; x = 1.48 \times 10^{-6}\\x = 0.0241$

Thus it takes $0.0241 \; \text{L}$ of sodium hydroxide to produce this buffer solution.

6 0

3 years ago

Ricardo compra un gaseosa en el súper al destaparla la gaseosa comienza a salir espuma y vuelca la mitad al piso ¿Por qué puede

dimaraw [331]

Answer:

Las bebidas gaseosas como las gaseosas están hechas de un soluto de dióxido de carbono gaseoso en un líquido. La solubilidad del dióxido de carbono en el líquido depende de la presión y la temperatura de la lata de refresco, y también de agitar la lata de refresco que introduce burbujas que permanecen ocultas hasta que se abre la lata antes de que burbujee.

Por lo tanto, dado que la presión en la lata de refresco permanece constante, elevar la temperatura, agitar la lata de refresco o congelar el refresco, lo que aumenta la cantidad de dióxido de carbono en la porción líquida, hará que el refresco forme espuma y se derrame.

Explanation:

8 0

3 years ago

PLEASE HELP ME ANSWER THIS ASAP! !​

PLEASE HELP ME ANSWER THIS ASAP! !