Answer:
Repolarization
Explanation:
Complete repolarization is achieved by the sodium pump. This actively pumps all the Na+ ti the outside and all the K+ to the inside. The pump requires energy in the form of ATP and is inhibited by metabolic poisons. Entry of Na+ is immediately followed by an increase in the permeability of the membrane to K+. These diffuse rapidly to the outside due to the concentration gradient. Being positively charged, the K+ reverses the polarity of the membrane making the outside positive.
Answer:
i) Rusting occurs the least in tubes 2 and 3 because either of air and water which are necessary for rusting is absent in the two tubes respectively.
ii) Rusting occurs most in tube 1 because both air and water which are necessary for rusting are present.
Explanation:
Rusting is a chemical change which involves a redox reaction. During the process of rusting, metallic iron is oxidized to hydrated iron (iii) oxide by oxygen present in air.
For rusting to take place effectively, each of these three factors mist be available: metallic iron, oxygen and water.
In the figure above, the iron nails in the three tester tubes will rust to different extents based on the availability of the three factors.
In test tube 1, the iron nails will rust the most because all the three factors: metallic iron, oxygen present in air, and water are abundantly present.
In test tube 2, the iron nails will rust the least or not at all because boiling of water removes dissolved oxygen from water and the oil layer above the boiled water prevents entry of oxygen from air. Thus, the nail do not rust because one of the three factors for rusting to take place, in this instance, oxygen is absent.
In test tube 3, the iron nails rusts the least or not at all as well because moisture or water is absent. Calcium chloride, a drying agent removes all the moisture from inside the tube. Hence, even though air is present, rusting do not occur as there is no moisture or water present.
The answer would be: <span>transgenic
</span>
Bacteria can be altered to produce a specific protein by introducing a sequence of DNA into their genes. This bacteria is called genetically modified bacteria. Bacteria that producing insulin called transgenic because they have genes of other species transplanted on them.
Answer:
I would.
Explanation:
Saving the environment is really important. The only downside would be only being able to use it during the day.
Answer:
1) CO₂
2) 0.2551 g
Explanation:
The balanced reactions are:
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂
MgCO₃ + 2HCl → MgCl₂ + H₂O + CO₂
1) The gas produced is CO₂.
2) Calculate mass of CaCO₃:
(0.5236 g) (0.4230) = 0.2215 g CaCO₃
Convert to moles:
(0.2215 g CaCO₃) (1 mol / 100.1 g) = 0.002213 mol CaCO₃
Find moles of CaCO₃:
(0.002213 mol CaCO₃) (1 mol CO₂ / mol CaCO₃) = 0.002213 mol CO₂
Convert to mass:
(0.002213 mol CO₂) (44.01 g / mol) = 0.09738 g CO₂
Calculate mass of MgCO₃:
(0.5236 g) (0.5770) = 0.3021 g MgCO₃
Convert to moles:
(0.3021 g MgCO₃) (1 mol / 84.31 g) = 0.003583 mol MgCO₃
Find moles of MgCO₃:
(0.003583 mol MgCO₃) (1 mol CO₂ / mol MgCO₃) = 0.003583 mol CO₂
Convert to mass:
(0.003583 mol CO₂) (44.01 g / mol) = 0.1577 g CO₂
Total mass of CO₂:
0.09738 g CO₂ + 0.1577 g CO₂ = 0.2551 g CO₂
