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nevsk [136]
3 years ago
15

How to tell if a reaction is exothermic.

Chemistry
2 answers:
tresset_1 [31]3 years ago
6 0

Answer:

If the reaction loses heat it is exothermic.

natta225 [31]3 years ago
5 0
If the enthalpy change listed for a reaction is negative, then that reaction releases heat as it proceeds — the reaction is exothermic (exo- = out). If the enthalpy change listed for the reaction is positive, then that reaction absorbs heat as it proceeds — the reaction is endothermic (endo- = in).
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Which root word of the binary ionic compound ends with -ide?
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The positive ion Yeah
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Colin is helping the librarian return books
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Explanation:

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Suppose a salt and a glucose solution are separated by a membrane that is permeable to water but not to the solutes. the nacl so
stira [4]
1)

<span>m(NaCl) = 1.95 g
V(H2O) = 250mL
M(NaCl) = </span><span>58.5 g/mole

Since waters density value is 1g/mL, it can be assumed that volume and mass of water are same values:

</span>V(H2O) = 250ml = 250g = 0.25 kg<span>

</span><span>molality of NaCl:
</span><span>
n(NaCl)=m/M=1.95/58.5= 0.033 mole

</span>molality b(NaCl)=n(NaCl) / V (H2O)= 0.033/0.25 = 0.132 mol/kg
<span>
milimolality of NaOH = 0.132/0,001 = 132 mmole/kg
</span>
milliosmolality of NaOH = milimolality x N of ions formed in dissociation

Since NaCl dissociates into 2 ions in solution:
<span>                                        
</span>milliosmolality of NaOH = 132 x 2 = 264  osmol<span>es/kg
</span>
2)

m(gl) = 9 g
V(H2O) = 250mL
M(NaCl) = 180 g/mole

Since waters density value is 1g/mL, it can be assumed that volume and mass of water are same values:

V(H2O) = 250ml = 250g = 0.25 kg

molality of glucose:

n(gl)=m/M=9/180= 0.05 mole

molality b(gl)=n(gl) / V (H2O)= 0.05/0.25 = 0.2 mol/kg

milimolality of glucose = 0.132/0,001 = 200 mmole/kg

milliosmolality of glucose = milimolality x N of ions formed in dissociation

Since glucose does not dissociate, milimolality and milliosmolality are same:
                                        
milliosmolality of glucose = 200 osmoles/kg

3)

The osmosis represents the diffusion of solvent molecules through a semi-permeable membrane that allows passage solvent molecules but does not to the dissolved substance molecule. The osmosis occurs when the concentrations of the solution on both sides of the membrane are different. Since the semi-permeable membrane only permeates the solvent molecules, but not the particles of the dissolved substance, it occurs the solvent diffusion through the membrane, i.e. the solvent molecules pass through the membrane to equalize the concentration on both sides of the membrane. Solvents molecules move from the middle with a lower concentration in the middle with a higher concentration of dissolved substances.

In our case, osmosis will occur because the concentration of NaCl solution and the concentration of glucose solution do not have same values. Osmosis will occur in the direction of glucose solution because it has a lower concentration.

3 0
4 years ago
A chemist requires 0.802 mol Na2CO3 for a reaction. How many grams does this correspond to?
Komok [63]

Answer:

Ok:

Explanation:

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7 0
3 years ago
Why is stability of compounds essential
yuradex [85]

Answer:

chemical stability is important to consider in the comprehensive assessment of pharmaceutical properties, activity, and selectivity during drug discovery.

7 0
3 years ago
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