Answer:
MoO₃
Explanation:
To solve this question we must find the moles of molybdenum in Mo2O3. The moles of Mo remain constant in the new oxide. With the differences in masses we can find the mass of oxygen and its moles obtaining the empirical formula as follows:
<em>Moles Mo2O3 -Molar mass: 239,878g/mol-</em>
11.79g * (1mol / 239.878g) = 0.04915 moles Mo2O3 * (2mol Mo / 1mol Mo2O3) = 0.09830 moles Mo
<em>Mass Mo in the oxides:</em>
0.09830 moles Mo * (95.95g/mol) = 9.432g Mo
<em>Mass oxygen in the new oxide:</em>
14.151g - 9.432g = 4.719g oxygen
<em>Moles Oxygen:</em>
4.719g oxygen * (1mol/16g) = 0.2949 moles O
The ratio of moles of O/Mo:
0.2949molO / 0.09830mol Mo = 3
That means there are 3 moles of oxygen per mole of Molybdenum and the empirical formula is:
<h3>MoO₃</h3>
Answer:
64,433.6 Joules
Explanation:
<u>We are given</u>;
- Volume of water as 220 mL
- Initial temperature as 30°C
- Final temperature as 100°C
- Specific heat capacity of water as 4.184 J/g°C
We are required to calculate the amount of heat required to raise the temperature.
- We know that amount of heat is calculated by;
Q = mcΔT , where m is the mass, c is the specific heat, ΔT is the change in temperature.
Density of water is 1 g/mL
Thus, mass of water is 220 g
ΔT = 100°C - 30°C
= 70°C
Therefore;
Amount of heat, Q = 220g × 4.184 J/g°C × 70°C
= 64,433.6 Joules
Thus, the amount of heat required to raise the temperature of water is 64,433.6 Joules
<span>Molds are created to achieve a
specific design of a material. These materials either came from a process of
having a higher or lower temperature. Therefore, the molder must have thermal
resistant properties. Low melting points means that the material to be shaped
came from a cooler process. Wood and metal have higher thermal conductivity and
therefore can easily be cooled. The wax can turn really hard and can be
unbreakable when present in colder materials due to the lipids present in it. Clay
however can become a mold because of its low melting point.</span>
20 grams of borax contains (20.0g) / (201 g mol -1) =0.10 mol of borax.
Therefore 0.40 mol of borax
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