Answer:
2Al+ 6HNO3 ---- 3H2 + 2Al(NO3)3
Explanation:
Put coefficient a,b,c, and d for calculation:
a Al + b HNO3 = c H2 + d Al(NO3)3
for Al: a = d
for H: b = 2c
for N: b = 3d
for O: 3b = 9d
Suppose a=1, then d=1, b=3, c=3/2
multiply 2 to make all natural number, a=2, then b=6, c=3, d=2
1. Decreases by 4. (B)
2. The atomic number changes. (B)
3. 56/26 Fe. (C)
4. Potassium-40;t1/2=25 days. (B)
5. Takes place in the upper atmosphere. (A)
Cold blooded animal? it’s a bit vague sorry
Answer:
All of the above processes have a ΔS < 0.
Explanation:
ΔS represents change in entropy of a system. Entropy refers to the degree of disorderliness of a system.
The question requests us to identify the process that has a negative change of entropy.
carbon dioxide(g) → carbon dioxide(s)
There is a change in state from gas to solid. Solid particles are more ordered than gas particles so this is a negative change in entropy.
water freezes
There is a change in state from liquid to solid. Solid particles are more ordered than liquid particles so this is a negative change in entropy.
propanol (g, at 555 K) → propanol (g, at 400 K)
Temperature is directly proportional to entropy, this means higher temperature leads t higher entropy.
This reaction highlights a drop in temperature which means a negative change in entropy.
methyl alcohol condenses
Condensation is the change in state from gas to liquid. Liquid particles are more ordered than gas particles so this is a negative change in entropy.
<h3><u>Answer;</u></h3>
The statements that are True are;
- Upon binding a molecule of oxygen, Hb undergoes a conformational change that makes the binding of subsequent O2 molecules easier.
- The conformational change induced in Hb upon binding oxygen is the result of a small movement (0.2 Å) of the iron cation in the center of heme.
- Site-directed mutagenesis studies have indicated that the cooperativity of O2 binding in Hb is attributable to the movement of the F helix in Hb.
<h3><u>Explanation</u>;</h3>
- Hemoglobin is a key pigment in the blood that transports oxygen gas to all the tissues in the body. It is made up of two types of chains; that is two alpha chains and two beta chains.
- in its deoxygenated state hemoglobin has a low affinity for oxygen compared to myoglobin. When oxygen is bound to the first subunit of hemoglobin it leads to subtle changes to the quaternary structure of the protein. This in turn makes it easier for a subsequent molecule of oxygen to bind to the next subunit.
