Answer:
A. + 6.
B. + 3.
Explanation:
<em>A. K₂CrO₄:</em>
- To calculate the oxidation no. of an element in a compound:
<em>We have that the sum of the oxidation no. of different elements in the compound multiplied by its no. is equal to the overall charge of the compound.</em>
∵ 2(oxidation no. of K) + (oxidation no. of Cr) + 4(oxidation no. of O) = 0.
oxidation no. of K = + 1, oxidation no. of O = - 2.
∴ 2(+ 1) + (oxidation no. of Cr) +4(- 2) = 0.
∴ 2 + (oxidation no. of Cr) - 8 = 0.
∴ (oxidation no. of Cr) - 6 = 0.
<em>∴ oxidation no. of Cr = + 6.</em>
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<em>B. Cr₂O₃:</em>
∵ 2(oxidation no. of Cr) + 3(oxidation no. of O) = 0.
oxidation no. of O = - 2.
∴ 2(oxidation no. of Cr) + 3(- 2) = 0.
∴ 2(oxidation no. of Cr) - 6 = 0.
∴ 2(oxidation no. of Cr) = + 6.
<em>∴ (oxidation no. of Cr) = + 6/2 = + 3.</em>
Answer:
c) disaccharides have more chemical bonds
Explanation:
disaccharides are made from the condensation of two monosaccharides.
This means there are more bonds in disaccharides. More bonds mean greater energy and vice versa .
The frequency of collisions between the N₂ and H₂ molecules will decrease and the rate of reaction will also decrease.
Since the water is cooler than the gas mixture, heat will flow from the gas to the water.
The gas will cool down, so the average kinetic energy of the gas molecules will decrease.
The molecules will be moving more slowly, so there will be <em>fewer collisions</em> and <em>fewer of these collisions will have enough energy to react</em>.
The rate of reaction between H₂ and N₂ molecules at room temperature is exceedingly slow, <em>but cooling the gas mixture will make the reaction even slower</em>.
<span>it is 3/6 = 0.5 mol/kg of solvent i.e. 0.5 molal <span>solution</span></span>
To cause death within hours of exposure to radiation, the dose needs to be very high, 10Gy or higher, while 4-5Gy will kill within 60 days, and less than 1.5-2Gy will not be lethal in the short term. However all doses, no matter how small, carry a finite risk of cancer and other diseases. Patients exposed to radiation between 8 to 30 Gy experience nausea and severe diarrhea within an hour, and they die between 2 days and 2 weeks after exposure. Absorbed doses greater than 30 Gy cause neurological damage
