Answer:
the percentage of carpet is calcium carbonates is 12.456734190
% H = 100 - ( 52.14 + 34.73 )=13.13 %
<span>assume 100 g of this compound </span>
<span>mass H = 13.13 g </span>
<span>moles H = 13.13 g / 1.008 g/mol=13 </span>
<span>mass C = 52.14 g </span>
<span>moles C = 52.14 g/ / 12.011 g/mol=4 </span>
<span>mass O = 34.73 g </span>
<span>moles O = 34.73 g/ 15.999 g/mol=2 </span>
<span>the empirical formula is C4H13O2</span>
Answer:
THEY ALL INVOLVE FIGHTING PATHOGENS
Explanation:
The immune system which is involved in defending the body against infections are diseases involves three lines of defense which are all involved in fighting against pathogens. Pathogens are invaders which when introduced into the body causes harm and therefore makes us sick. The body's first line of defense includes the physical barriers such as the skin, mucous membrane; chemical barriers such as tears, saliva, gastric acid in the stomach. These helps to keep the pathogens from entering the delicate parts of the body and once the pathogens find their way out of the reach of the first line of defense, the second line of defense is initiated. This includes inflammatory effects, swelling, redness, phagocytosis by neutrophils and macrophages. The third line of defense is the actions of lymphocytes which acts on invading microbes. The lymphocytes are of two types; the B and T cells. B cells produces antibodies which fight the antigens and T cells attack the infected cells of the body. There is also the memory cells which keeps information about the invading microbes for future attacks. This enables the body to respond swiftly when next the same type of pathogens attack.
CBr4 is a symmetric tetrahedral molecule so it will be non-polar.
Answer:
c and d are correct
Explanation:
In A, false because in Valence Electrons, the more the valences, the more stable an atom is.
In B, false because atoms cannot readily gain or lose valence electrons as the number of valence electrons is determined by the column they are in.
In C, true because the more the valence electrons, the more the stability of an atom.
In D, true as electron placing is important and the reactivity of an atom is important.
So C and D are true!
