Answer:
Animals gain energy from the food they eat. Some animals eat plants while others eat other animals. This is passing of energy from the sun to plants to animal to other animals is called a food chain
Answer:- partial pressure of Kr = 0.306 atm, partial pressure of oxygen = 0.264 atm and partial pressure of carbon dioxide = 0.396 atm
Total pressure is 0.966 atm
Solution:- moles of Kr = 21.7 g x (1mol/83.8g) = 0.259 mol
moles of oxygen = 7.18 g x (1mol/32g) = 0.224 mol
moles of carbon dioxide = 14.8 g x (1mol/44g) = 0.336 mol
Volume of container = 23.1 L and the temperature is 59 + 273 = 332 K
From ideal gas law equation, P = nRT/V
partial pressure of Kr = (0.259 x 0.0821 x 332).23.1 = 0.306 atm
partial pressure of oxygen = (0.224 x 0.0821 x 332)/23.1 = 0.264 atm
partial pressure of carbon dioxide = (0.336 x 0.0821 x 332)/23.1 = 0.396 atm
Total pressure of the gas mixture = 0.306 atm + 0.264 atm + 0.396 atm = 0.966 atm
Answer:
a) Can be cut into tiny pieces - Physical Change
b) Fizzling occurs when placed water -Chemical Change
c) Light is emitted when burned -Chemical Change
d) Turns to ash -Chemical Change
Explanation:
Answer:
v = 16 m/s
Explanation:
Given that,
Distance, d = 400 m
Time taken, t = 25 s
We need to find the speed of the horse. Speed is equal to distance covered divided by time taken. So,
So, the speed of the horse is 16 m/s.
Answer: pH = 6.77
Explanation:
1) <u>Chemical equilibrium</u>
- 2 H₂O (l) ⇄ H₃O⁺ (aq) + OH⁻ (aq)
2) <u>Equilibrium constant, Kw</u>
- By stoichiometry [H₃O⁺] = [OH⁻]. Call it x
- x = √ (2.92 × 10⁻¹⁴) = 1.709 × 10⁻⁷ M = [H₃O⁺]
3)<u> pH</u>
- pH = - log [H₃O⁺] = - log (1.709 × 10⁻⁷) = 6.77
