Answer:
The four characrteristics of warm blooded animals are÷
Explanation:
i=They can keep its body temperature the same no matter what the outside temperature .
ii=They can maintain a constant body temperature.
iii=They obtain energy from food consumption.
iv=They maintain their body temperature higher than environment.
Answer:
0.2 mL stock solution, 0.8 solvent, 0.1 mL first solution and 0.9 solvent
Explanation:
The final volume for fist solution is 1 mL and concentration must will be 1/5, then 1 mL/5=0.2 mL. For complete the 1 mL add the missing solvent volume 1 mL-0.2 mL=0.8 mL. For second solution, assuming final volume is 1 mL, and concentration 1/10, then we have 1 mL /10=0.1 mL solution 1/5. Completing volume, 1 mL-0.1 mL= 0.9 mL solvent.
To fully understand the problem, we use the ICE table to identify the concentration of the species. We calculate as follows:
Ka = 2.0 x 10^-9 = [H+][OBr-] / [HOBr]
HOBr = 0.50 M
KOBr = 0.30 M = OBr-
<span> HOBr + H2O <-> H+ + OBr- </span>
<span>I 0.50 - 0 0.30 </span>
<span>C -x x x
</span>---------------------------------------------
<span>E(0.50-x) x (0.30+x) </span>
<span>Assuming that the value of x is small as compared to 0.30 and 0.50 </span>
<span>Ka = 2.0 x 10^-9 = x (0.30) / 0.50) </span>
<span>x = 3.33 x 10^-9 = H+</span>
pH = 8.48
Answer:
The rate of leakage will be higher for helium; its molecules move about 3 times faster than oxygen’s
Explanation:
Step 1: Data given
Molar mass helium = 4.0 g/mol
Molar mass O2 = 32 g/mol
Step 2: Graham's law
Graham's Law of Effusion states that the rate of effusion of a gas is inversely proportional to the square root of the molecular mass : 1/(Mr)^0.5
Rate of escape for He = 1/(4.0)^0.5 = 0.5
Rate of escape for O2 = 1/(32)^0.5 = 0.177
The rate of leakage will be higher for helium; its molecules move about 3 times faster than oxygen’s
