Based on your observations, do you think any of the samples are the same substance?

Which of the following items would dissolve most quickly in a glass of warm water?

andrezito [222]

Answer:

A. a spoonful of granulated sugar

Explanation:

hope that helps :)

4 0

3 years ago

Use the following information S(s)+O2(g)→SO2(g), ΔH∘ = -296.8kJ SO2(g)+12O2(g)→SO3(g) , ΔH∘ = -98.9kJ to calculate ΔH∘f for H2SO

Irina-Kira [14]

Answer : The enthalpy of formation of $H_2SO_4$ is, -812.4 kJ/mole

Explanation :

According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.

According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.

The formation of $H_2SO_4$ will be,

$S+H_2+2O_2\rightarrow H_2SO_4$ $\Delta H_{formation}=?$

The intermediate balanced chemical reaction will be,

(1) $S+O_2\rightarrow SO_2$ $\Delta H_1=-298.2$

(2) $SO_2+\frac{1}{2}O_2\rightarrow SO_3$ $\Delta H_2=-98.2$

(3) $SO_3+H_2O\rightarrow H_2SO_4$ $\Delta H_3=-130.2$

(4) $H_2+\frac{1}{2}O_2\rightarrow H_2O$ $\Delta H_4=-285.8$

Now adding all the equations, we get the expression for enthalpy of formation of $H_2SO_4$ will be,

$\Delta H_{formation}=\Delta H_1+\Delta H_2+\Delta H_3+\Delta H_4$

$\Delta H=(-298.2)+(-98.2)+(-130.2)+(-285.8)$

$\Delta H=-812.4kJ/mol$

Therefore, the enthalpy of formation of $H_2SO_4$ is, -812.4 kJ/mole

3 0

3 years ago

Round 0.007062 to 4 significant numbers

mafiozo [28]

Answer

its already rounded

Explanation:

8 0

3 years ago

at stp which of following would have the same number of molecules a 1 l of c2h4 gas? a. 0.5 of H2 b. 1L of Ne c.2L of H2O d.3L o

sashaice [31]

Answer:d

Explanation:

4 0

3 years ago

The Nuremberg War Crimes trials established

ra1l [238]

The Nuremberg War Crimes trials established the international legal precedent that individuals who violate human rights can be held responsible for their actions. The correct option in regards to all the options given in the question is option "2". The Nuremberg trials were held against the Germans by the Allied forces against the war crimes done by the Germans during World War II. Many of the allied countries were in favor of killing the war criminals before any trial, but ultimately the trial was held and the criminals were either hanged to death of were killed by the firing squad.

7 0

3 years ago