D. Cell membrane: surrounds a cell and allows substances to pass in and out
Answer:
H₂CO₃→H₂O + CO₂
Exphlanation:
Soda is carbonated water. It contains carbon dioxide dissolved in water , which is carbonic acid. On opening the soda, the carbonic acid undergoes the reverse reaction and releases carbon dioxide in the air . The soda is thus left with just water and loses it's fizz.
Answer:
Cranberry juice is a homogeneous mixture.
Explanation:
Cranberry juice is a clear, red liquid. It is a homogeneous mixture, because you can't see a boundary between the water and the dissolved red substances dissolved in the water.
A is wrong. In oatmeal with raisins, you can tell the raisins from the oatmeal (see below).
C is wrong. Milk is a suspension of fat globules in an aqueous solution of other substances
D is wrong. Pepsi in an unopened bottle is a homogeneous, clear brown aqueous solution of carbon dioxide, high fructose corn syrup, and other substances.
Answer:
The system gains 126100 J
Explanation:
The heat can be calculated by the equation:
Q = nxCxΔT, where Q is the heat, C is the heat capacity,n is the number of moles and ΔT is the variation of temperature (final - initial). The number of moles is the mass divided by the molar mass, so:
n = 250/4 = 62.5 mol.
The system must be in thermal equilibrium with the surroundings, so if the temperature of the surroundings decreased 97 K, the temperature of the system increased by 97 K, so ΔT = 97 K
Q = 62.5x20.8x97
Q = 126100 J
In the first shell there is 2 electrons and on the second shell there is 4 elections.
