It was referred to as the Homo erectus.
<h3><u>
The following events are identified as chemical weathering:</u></h3>
- The minerals in a marble statue react with water to form acids and pores in the structure.
- The rocks in a region are streaked orange after being exposed to repeated rains.
<em><u>Reason: </u></em>
When the weathering process occurs due to <em>chemical reaction</em>, then it is considered as chemical weathering.
In <em>the first case</em>, minerals of marble statue are <em>reacting</em> with water to cause weathering. In the <em>second case</em>, due to the <em>acidificaion reaction</em>, the change of the color has happened after exposure to the repeated rains.
<h3><u>
The following events are identified as Mechanical weathering:</u></h3>
- A piece of rock crumbles after being constantly thrashed by strong waves.
- Industrial runoff forms cracks in a rocky structure in its path.
<em><u>Reason:</u></em>
When the rock is broken into simple pieces <em>without any chemical reaction </em>it is considered as mechanical weathering.
In the <em>first cause</em>, due to the <em>abrasion</em> caused by the strong waves, weathering has happened, in the <em>second case</em> industrial run off may be of varying temperature and thus may cause <em>heating or cooling</em> of the rock and causes weathering.
A toxin or other foreign substance which induces an immune response in the body, especially the production of antibodies.
Answer:
The correct answer is - 38.15 gm of NaCl.
Explanation:
Write the balanced equation for this reaction of sodium (Na) and chlorine (Cl₂) to produce sodium chloride (NaCl):
2Na + Cl₂ —> 2NaCl
the mass of Na and the mass of NaCl :
Molar mass of Na = 23 g/mol
In the balanced equation = 2 × 23 = 46 g
Molar mass of NaCl = 23 + 35.5
= 58.5 g/mol
similarly in balanced equation = 2 × 58.5 = 117 g
From the balanced equation above,
46 g of Na reacted to produce 117 g of NaCl.
By converting it to 15 grams of Na.
Therefore,15 g of Na will react to produce = (15 × 117)/46 = 38.15 g of NaCl.
Thus, 38.15 g of Na
Answer:
Brassica species are dicot which means that they have two cotyledons instead of one like monocots. Cotyledons supply food for the plants in the seed. As the plant matures, it flowers. Mustard plants have small yellow flowers in clusters.