Answer:
<u>A. Magnet has a north pole and south pole.</u>
Explanation:
- A magnet has a north and south pole
- Magnets attract paper clips due to the metals present
- Magnetic fields are not visible
- North pole and south pole attract each other
Only the first statement is correct, the answer is (A).
The answer would be D.
SiCl4 + 2H2O → SiO2 + 4HCl (balanced equation)
The term "solution" is more frequently used when a homogeneous mixture<span> is a liquid, although it is sometimes used if the </span>homogeneous mixture<span> is a gas.</span>
Answer:
3.0 x 10²⁴molecules
Explanation:
Given parameters:
Number of moles of compound = 5moles
Unknown:
Number of molecules = ?
Solution:
A mole is substance that contains the Avogadro's number of particles;
1 mole = 6.02 x 10²³ molecules
5 moles of the compound will give 5 x 6.02 x 10²³ molecules
= 3.0 x 10²⁴molecules
Answer:
A protein has four subunits whose molecular masses are 140, 80, and 60 kDa.
A disulfide bond links the two 80 kDa subunits (possibly identical).
Explanation:
Given that:
A protein has four subunits whose molecular masses are 140, 80, and 60 kDa.
A disulfide bond links the two 80 kDa subunits (possibly identical).
As a result of SDS and dithiothreitol analysis treatment, the molecular masses can not be 360 in total. They are 280, which implies that they are in short of 80 kDa. This means that there are possibilities that two groups with a molecular mass of 80 kDa which are joined by a disulfide bond.
The presence of SDS and dithiothreitol acts as a reducing agent, and they can break disulfide bonds whose pH is greater than 7, i.e. those in basic condition.
