Answer:
d) the signals must be changed to another form at ground stations to travel through space.
Explanation:
Spacecraft use transmitters to communicate with people on Earth. This are sent in the form of signals.
Question:
Which of the following statements correctly describe(s) the driving forces for diffusion of Na+ and K+ ions through their respective channels? Select all that apply.
A)The diffusion of Na+ ions into the cell is facilitated by the Na+ concentration gradient across the plasma membrane.
B)The diffusion of Na+ ions into the cell is impeded by the electrical gradient across the plasma membrane.
C)The diffusion of K+ ions out of the cell is impeded by the K+ concentration gradient across the plasma membrane.
D)The diffusion of K+ ions out of the cell is impeded by the electrical gradient across the plasma membrane. The electrochemical gradient is larger for Na+ than for K+.
Answer:
"The concentration gradient and the electro-chemical gradient" describes the driving forces for diffusion of Na+ and K+ ions through their respective channels
Explanation:
The Na ions diffusion inside the cell is facilitated by the concentration gradient of the Na ions which is present across the plasma membrane. Hence, the diffusion of the K ions which is present outside the cell and will be impeded due to the electrical gradient which is present near the plasma membrane. Thus, the electro-chemical gradient is greater as compared to the Na ion than that of the K ion.
<h3>
Answer:</h3>
A. 1.4 V
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Explanation:</h3>
We are given the half reactions;
Ni²⁺(aq) + 2e → Ni(s)
Al(s) → Al³⁺(aq) + 3e
We are required to determine the cell potential of an electrochemical cell with the above half-reactions.
E°cell = E(red) - E(ox)
From the above reaction;
Ni²⁺ underwent reduction(gain of electrons) to form Ni
Al on the other hand underwent oxidation (loss of electrons) to form Al³⁺
The E.m.f of Ni/Ni²⁺ is -0.25 V and that of Al/Al³⁺ is -1.66 V
Therefore;
E°cell = -0.25 V - (-1.66 V)
= -0.250V + 1.66 V
= + 1.41 V
= + 1.4 V
Therefore, the cell potential will be +1.4 V
Answer:
OH^-
Explanation:
Any substance that is able to neutralize acidity in the stomach is generally known as an antacid. There are various kinds of antacids that are in common use. It should be noted that the stomach is usually slightly acidic.
Milk of magnesia is the substance magnesium hydroxide with chemical formula Mg(OH)2. A solution of milk of magnesia contains Mg^2+ and OH^-.
Hence the negative ion contained in milk of magnesia is the hydroxide ion OH^-.
Answer: 41.5 mL
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
where,
n = moles of solute
= volume of solution in L
Given : 59.4 g of 
in 100 g of solution
moles of 
Volume of solution =
Now put all the given values in the formula of molality, we get
To calculate the volume of acid, we use the equation given by neutralisation reaction:
where,
are the molarity and volume of stock acid which is
are the molarity and volume of dilute acid which is
We are given:
Putting values in above equation, we get:
Thus 41.5 mL of the solution would be required to prepare 1550 mL of a .30M solution of the acid
