In order to find the density of an object, you need to know the mass of the object and the volume.
That is why the unit of density is kg/m3.
Hope it helps
No of moles of MgCl2 = weight of MgCl2 / Molecular weight of MgCl2
Weight of MgCl2 =moles of MgCl2 x molecular mass of MgCl2
= 8.90 x 95=845.5 gm
Answer: option <span>C. the total energy inside the calorimeter will decrease.
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Justification:
The answer is a direct application of the first law of thermodynamic (the law of conservation of energy).
By telling that the t<span>he calorimeter is sealed so that there is no heat exchanged between the contents of the container and the surrounding air, the first law of thermodynamics implies that the total energy inside the calorimeter will not change.
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<span>That statement, without adding any more is enough justification.
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Regarding, the other statements, you can show they are true:
<span>A.
the thermometer will show an increase in temperature.
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</span><span>Since the reaction is exothermic, the heat released will increase the temperature inside the sealed calorimeter,which, of course, is shown by the termometer.
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</span><span>B. The potential
energy of the products will be lower than that of the reactants.
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</span><span>In any exothermic reaction, the potential energy of the products is lower than that of the reactants, because the heat released is lost by the reactants when they react and transform into the products.
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</span><span>D. The water
increases in temperature as the reaction gives off heat</span>.
Sure. The heat cannot leave the sealed calorimeter, but the water inside the calorimeter will absorb that heat: the molecules of water will gain kinetic energy and so its temperature will be increase.
Answer:
9.
a. NH2CH2COOH
b. The function group is what I put in bold.
c. carboxylic acid and amine
10.
a. NH2CH(CH3)COOH
b. The functional group is in bold.
c. carboxylic acid and amine
Explanation:
NH2 is amine (amino acid)
COOH is the carboxylic acid (acetic acid)
Answer: Electrovalent or Ionic Compounds
Explanation:
Electrovalent Compounds Form bonds that are characterised by transfer of electrons from metallic atoms to non-metal licenses atoms during a chemical reaction.
The metallic atom after donating their valence electrons, become positively charged, while the non-metal license atoms becomes negatively charged after acquiring extra electrons.
A typical example of electrovalent compounds can be found between the association of Group 1(Alkali Metals) elements and the Group 7(Halogen Family) elements.