The amount of W(OH)2 needed would be 448.126 g
<h3>Stoichiometric calculation</h3>
From the equation of the reaction:
W(OH)2 + 2 HCl → WCl2 + 2 H2O
The mole ratio of W(OH)2 to HCl is 1:2
Mole of 150g HCl = 150/36.461
= 4.11 moles
Equivalent mole of W(OH)2 = 4.11/2
= 2.06 moles
Mass of 2.06 moles W(OH)2 = 2.06 x 217.855
= 448.188g
More on stoichiometric calculations can be found here: brainly.com/question/8062886
"Polysaccharide carbohydrate" comprises an S. pneumoniae capsule.
<u>Option:</u> C
<u>Explanation:</u>
The lengthy sequences of carbohydrate molecules, primarily polymeric carbohydrates constructed of units of monosaccharides linked together through glycosidic connections, understood as Polysaccharides. This carbohydrate can respond to water by catalyzing amylase enzymes, which generate component sugars.
A major human pathogen is Streptococcus pneumoniae or pneumococcus. The virulence is primarily due to its polysaccharide envelope, which protects it from the recipient immune response, and this has led to comprehensive study of the shell.
The percentage of Chromium in Chromium Oxide is calculated as follow,
Step 1: Calculate Molar mass of Cr₂O₃,
Cr = 51.99 u
O = 16 u
So,
2(51.99) + 3(16) = 103.98 + 48 = 151.98 u
Step 2: Secondly divide molar mass of only chromium with total mass of Cr₂O₃ and multiply with 100.
i.e.
=

× 100
=
68.41 %
So, the %age composition of chromium in chromium oxide is
68.41 %.