Answer:
Ver explicación
Explanation:
El método científico se refiere al patrón establecido de resolución de un problema científico. Los siguientes son pasos importantes en el método científico;
Haz una observación.
formular preguntas relevantes.
elabore una hipótesis que pueda ser probada.
Diseña un experimento.
Prueba la hipótesis usando tu diseño experimental.
Teniendo en cuenta ambos escenarios, el último caso en el que estudiantes de diferentes capacidades trabajan juntos para resolver un problema refleja mejor el método científico porque pueden hacerse preguntas entre sí y llegar a hipótesis comprobables que pueden demostrarse como verdaderas o falsas mediante experimentos.
Answer:
Second order
Explanation:
We could obtain the order of reaction by looking at the table very closely.
Now notice that in experiment 1 and 2, the concentration of [OH^-] was held constant while the concentration of [S8] was varied. So we have;
a situation in which the rate of reaction was tripled;
0.3/0.1 = 2.10/0.699
3^1 = 3^1
Therefore the order of reaction with respect to [S8] is 1.
For [OH^-], we have to look at experiment 2 and 3 where the concentration of [S8] was held constant;
x/0.01 = 4.19/2.10
x/0.01 = 2
x = 2 * 0.01
x = 0.02
So we have;
0.02/0.01 = 2^1
2^1 = 2^1
The order of reaction with respect to [OH^-] = 1
So we have the overall rate law as;
Rate = k[S8]^1 [OH^-] ^1
Overall order of reaction = 1 + 1 = 2
Therefore the reaction is second order.
Answer:
The new volume of a gas at 750 mmhg and with a volume of 2. 00 l when allowed to change its volume at constant temperature until the pressure is 600 mmhg is 2.5 Liters.
Explanation:
Boyle's law states that the pressure of a given amount of gas is inversely proportional to it's volume at constant temperature. It is written as;
P ∝ V
P V = K
P1 V1 = P2 V2
Parameters :
P1 = Initial pressure of the gas = 750 mmHg
V1 = Initial pressure of the gas = 2. 00 Liters
P2 = Final pressure of the gas = 600 mmHg
V2 = Fimal volume of the gas = ? Liters
Calculations :
V2 = P1 V1 ÷ P2
V2= 750 × 2. 00 ÷ 600
V2 = 1500 ÷ 600
V2 = 2.5 Liters.
Therefore, the new volume of the gas is 2. 5 Liters.
Answer: option D. the ability of a base to react with a soluble metal salt.
Justification:
NaOH is a strong base, which means that in water it will dissociate according to this reaction:
- NaOH(aq) → Na⁺ (aq) + OH⁻ (aq)
On the other hand, CuSO₄ is a soluble ionic salt which in water will dissociate into its ions according to this other reaction:
Hence, in solution, the sodium ion (Na⁺) will react with the metal salt in a double replacement reaction, where the highly reactive sodium ion (Na⁺) will substitute the Cu²⁺ in the CuSO₄ to form the sodium sulfate salt, Na₂SO₄ (water soluble), and the copper(II) hydroxide, Cu(OH)₂ (insoluble).
That is what the given reaction represents:
CuSO₄ (aq) + 2NaOH(aq) → Cu(OH)₂(s) + Na₂SO₄(aq)
↑ ↑ ↑ ↑
soluble metal salt strong base insoluble base solube salt
The HCl added = 1.25 moles
and the moles of Na2HPO4 = 1 mole
Now when acid is added in the given solution of Na2HPO4
One mole of H+ will react with one mole of Na2HPO4 to given one mole of NaH2PO4
Na2HPO4 + H+ ---> NaH2PO4
Now this one mole formed NaH2PO4 will further react with 0.25 moles of H+ left to form 0.25 moles of H3PO4 and 0.75 moles of NaH2PO4 will remain in the solution
So this will result into formation of a buffer of phosphoric acid and NaH2PO4
NaH2PO4 + H+ ---> H3PO4
pKa of H3PO4 = 2.1
so pH = pKa + log [salt] / [acid] = 2.1 + log [0.75 / 0.25] = 2.58
so the pH will be in between 2.1 to 7.2