A 220.0 mL sample of helium gas is in a cylinder with a movable piston at 105 kPa and 275 K. The piston is

During the combustion of 2.00 g of coal, the temperature of 500 g of water inside the calorimeter increased from 25.0°c to 43.7°

pantera1 [17]

Answer is: 39,083kJ.
m(coal) = 2,00g.
m(water) = 500g.
ΔT = 43,7°C - 25°C = 18,7°C, <span>difference at temperatures.</span>
c(water) = 4,18 J/g·°C, <span>specific heat of water
</span>Q = m(water)·ΔT·c(water), heat of reaction.
Q = 500g·18,7°C·4,18J/g·°C.
Q = 39083J = 39,083kJ.

6 0

3 years ago

20 mL of Ba(OH)2 solution with unknown concentration was neutralized by the addition of 43.89 mL of a .1355 M HCl solution. Calc

bezimeni [28]

Answer:

Concentration of the barium ions = $[Ba^{2+}] = 0.4654 M$

Concentration of the chloride ions = $[Cl^{-}]=0.9308 M$

Explanation:

$Moles (n)=Molarity(M)\times Volume (L)$

Moles of hydrogen chloride = n

Volume of hydrogen chloride solution = 43.89 mL = 0.04389 L

Molarity of the hydrogen chloride = 0.1355 M

$n=0.1355 M\times 0.04389 L=0.005947 mol$

$Ba(OH)_2+2HCl\rightarrow BaCl_2+2H_2O$

According to reaction, 2 moles of HCl reacts with 1 mole of barium hydroxide.

Then 0.05947 moles of HCl will react with:

$\frac{1}{2}\times 0.05947 mol=0.029735 mol$ barium hydroxide

Moles of barium hydroxide = 0.029735 mol

$Ba(OH)_2(aq)\rightarrow Ba^{2+}(aq)+2OH^-(aq)$

1 mole of barium hydroxide gives 1 mole of barium ion in an aqueous solution. Then 0.029735 moles of barium hydroxide will give:

$=1\times 0.029735 mol= 0.029735 mol$

Volume of solution after neutralization reaction :

= 20.0 mL + 43.89 mL = 63.89 mL = 0.06389 L

Concentration of the barium ions = $[Ba^{2+}]$

$[Ba^{2+}]=\frac{0.029735 mol}{0.06389 L}=0.4654 M$

$Ba(Cl)_2(aq)\rightarrow Ba^{2+}(aq)+2Cl^-(aq)$

1 mole of barium chloride gives 1 mole of barium ions and 2 moles of chloride ions in an aqueous solution.

Then concentration of chloride ions will be:

$[Cl^-]=2\times [Ba^{2+}]=2\times 0.4654 M=0.9308 M$

8 0

3 years ago

Which compound forms from 2 parts of hydrogen and 1 part of oxygen?

lina2011 [118]

Water, H2O, HOH these are all the same compound just worded differently

6 0

3 years ago

Fill in the coefficients to balance the equation for the chemical reaction that occurs:

Dominik [7]

Answer:

The equation is balanced

Explanation:

NaCl (aq) + AgNO3(aq) ––> AgCl (s) + NaNO3 (aq)

NaCl (aq) + AgNO3 (aq)

Na = 1 , Cl=1 , Ag = 1 , No3= 1

AgCl (s) + NaNO3 (aq)

Ag = 1 , Cl=1 , Na = 1 , No3= 1

8 0

2 years ago

In the reaction N2 + 3H2 → 2NH3, what is the mole ratio of hydrogen to nitrogen?

uranmaximum [27]

Answer: The mole ratio of hydrogen to nitrogen is 3 mole: 1 mole, 3:1

Explanation:

•Mole ratios are determined using the coefficients of the substances in the balanced chemical equation. •Each coefficient represents the number of mole of each substance in the chemical reaction.

•The mole ratio can be determined by first writing out a balanced chemical equation for the reaction.

For this reaction the balanced chemical equation is

N2(g) + 3H2(g) ----> 2NH3(g)

1mol:3mol : 2mol

From the equation we can see that 1 mole of N2(g) reacts with 3 moles of H2(g) or 3 moles of H2(g) react with 1 mole of N2(g) to produce 2 moles of NH3(g).

Therefore, the mole ratio of hydrogen to nitrogen is 3 mole: 1 mole, 3:1

7 0

3 years ago