Answer:
true. I think
Explanation:
A chemical formula shows the atoms a molecule is made of.
<span>The student should
follow following steps to make 1 L of </span>2.0 M CaCl₂.<span>
<span>
1. First he should
calculate the number of moles of 2.0 M CaCl</span></span>₂ in 1 L solution.<span>
</span>Molarity of the solution = 2.0 M<span>
Volume of solution which should be prepared = 1 L
Molarity =
number of moles / volume of the solution
Hence, number of moles in 1 L = 2 mol
2. Find
out the mass of dry CaCl</span>₂ in 2 moles.<span>
moles =
mass / molar mass
Moles of CaCl₂ =
2 mol</span><span>
Molar mass of CaCl₂ = </span><span>110.98 g/mol
Hence, mass of CaCl</span>₂ = 2 mol x <span>110.98 g/mol
= 221.96
g
3. Weigh the mass
accurately
4. Then take a cleaned and dry1 L volumetric flask and place a funnel top of it. Then carefully add the salt into the volumetric flask and
finally wash the funnel and watch glass
with de-ionized water. That water also should be added into the volumetric
flask.
5. Then add some
de-ionized water into
the volumetric flask and swirl well until all salt are
dissolved.
<span>6. Then top up to
mark of the volumetric flask carefully.
</span></span>
7. As the final step prepared solution should be labelled.
Answer: The correct sequence for the series of event would be.
1. Igor's toe is being cut by the glass.
2. The wound surrounding the injury becomes infected with bacteria from Igor's foot.
3. Antibodies and circulating white blood cells stick to the bacteria creating a large complex in the lymph vessel.
4. The bacteria enter his lymph system and travel towards a lymph node.
5. The complex becomes trapped in a lymph node and is engulfed by a phagocyte.
6. The bacteria is destroyed.
Explanation:
Whenever there is any cut or wound in the body and body encounters invasion of the foreign materials it considers it as harmful pathogen.
These pathogens when enters the body it is considered as antigen, it then travels to the lymphatic system.
These bacterial complex is then killed by the phagocytes and digested by the body.
In this way the complex is killed and the bacteria is destroyed.
Answer:
Radiation is the transfer of heat between objects which are not touching. I think
Explanation: