Answer:
lead
Explanation:
lead have no reaction with Hcl unlike aluminum,zinc, magnesium... and it forms a black oxide
The mass in grams of one molecule of cholesterol, C27H46O is6.43×10⁻²² g
6.02×10²³ molecules = 1 mole of Cholesterol
But,
1 mole of Cholesterol = 387 g
Thus,
6.02×10²³ molecules = 387 g mole of Cholesterol
6.02×10²³ molecules = 387 g mole of Cholesterol
1 molecule = 387 / 6.02×10²³
1 molecule = 6.43×10⁻²² g of Cholesterol
Thus, the mass of 1 molecule of cholesterol is 6.43×10⁻²² g
Learn more about Avogadro's number:
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The molar mass of cholesterol = 386.654 g/mol = 387 g/mole
3.2 mg cholesterol x 1 g/1000 mg x 1 mole/387 g x 6.02x1023 molecules/mole = 5.0x1018 molecules.
a base
an acid
neutrality
The correct answer is:
neutrality
on the pH scale 7 is neutral above 7 is basic and below 7 is acidic.
Explanation:
The pH is an example of how acidic/basic water is. The scale goes from 0 - 14, with 7 being neutral, pH of less than 7 designates acidity, whereas a pH of greater than 7 intimates a base. pH is really a pattern of the relative amount of free hydrogen and hydroxyl ions in the water.pH is a measure of how acidic/basic water is.
It is neutral because, at this pH, the molar concentrations of Hydroxide and Hydronium are same, therefore the substance is not a base nor an acid.
On the pH scale, a 7 represents neutrality. It is not considered acidic nor basic, but instead, it represents a balanced solution, such as pure water.
On the pH scale, a 7 indicates neutrality. This means that the solution is neither acidic nor basic. The pH scale ranges from 0 to 14, with 7 being the midpoint. Solutions with a pH less than 7 are considered acidic, while those with a pH greater than 7 are considered base or alkaline. So, a pH of 7 is indicative of a perfectly balanced solution, like pure water.
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A. lithium, beryllium, and boron
B. nitrogen, arsenic, and antimony
C. potassium, calcium, and gallium
D. cesium, platinum, and radon
Answer: The correct answer is option B.
Explanation:
Elements which lie in the same group most likely have similar chemical properties.
From the given options:
Option 1: Lithium, beryllium and boron.
Lithium lies in Group 1, Beryllium in group 2 and boron in Group 13. As, these elements do not lie in the same group and hence, the properties of these elements will not be the same.
Option 2: Nitrogen, arsenic and antimony
All these elements lie in Group 15 of the periodic table and hence will have the same properties.
Option 3: Potassium, calcium and Gallium
Potassium lies in Group 1, Calcium in group 2 and Gallium in Group 13. As, these elements do not lie in the same group and hence, the properties of these elements will not be the same.
Option 4: Cesium, Platinum and Radon.
Cesium lies in Group 1, Platinum in group 10 and Radon in Group 18. As, these elements do not lie in the same group and hence, the properties of these elements will not be the same.
Therefore, the correct option is Option B.
Metal is most likely to be correct
Alkali metals
O Noble gases
O Transition metals