The best and most correct answer among the choices provided by the question is the second choice or letter B which is hand washing. Hand washing is the most natural way of preventing the risk of food-borne disease without<span> affecting the taste or nutrient content of foods such as lettuce and other vegetables.</span>
Answer:
<em>A solution containing 60 grams of nano3 completely dissolved in 50. Grams of water at 50°c is classified as being</em> <u>supersaturaded</u>
Explanation:
This question is about solubility.
Regarding solubility, the solutions may be classified as:
- Unsaturated: the concentration is below the maximum concentration permited at the given temperature.
- Saturated: the concentration is the maximum permitted at the given temperature, under normal conditions.
- Supersaturated: the concentration has overcome the maximum permitted at the given temperature. This is possible only under special conditions and is a very unstable state.
Each substance has its own, unique solubility properties. So, in order to tell the state of the solution you need to compare with either solubility tables, or solubility curves; or run you own experiments.
- In internet you can find the solubility curve of NaNO₃ showing the solubility for a wide range of temperatures.
- In such curve the solubility of NaNO₃ at 50°C is about 115 g of NaNO₃ per 100 g of water.
- Hence, do the proportion to determine the amount of solute that can be dissolved in 50 grams of water at 50°CÑ
115 g NaNO₃ / 100 g H₂O = x / 50 g H₂O ⇒ x = 57.5 g NaNO₃
- <u>Conclusion</u>: 50 grams of water can contain 57.5 g of NaNO₃ dissolved; so, <em>a solution containing 60 g of NaNO₃ completely dissolved in 50 grams of water is supersaturated.</em>
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Explanation:
An alpha particles is basically a helium nucleus and it contains 2 protons and 2 neutrons.
Symbol of an alpha particle is 
. Whereas a neutron is represented by a symbol 
, that is, it has zero protons and only 1 neutron.
Therefore, reaction equation when an aluminum- nuclide transforms into a phosphorus- nuclide by absorbing an alpha particle and emitting a neutron is as follows.
The Gulf Stream, warm current in the Atlantic
Answer:
2 Hertz
Explanation:
<em>The frequency would be 2 Hertz.</em>
<u>The frequency of a wave is defined as the rate at which the particles of a medium vibrates when the wave is passed through it while the period of a wave is the time it takes the particles to make a complete cycle of vibration.</u>
The frequency of a wave is inversely related to its period and is defined by the following equation:
f = 1/t, where f is the frequency (in hertz) and t is the period (in seconds).
Hence, if the period of a ripple is 1/2 or 0.5 seconds, the frequency becomes;
f = 1/0.5 = 2 Hertz
