There are two naturally occurring isotopes of gallium: mass of Ga-69 isotope is 68.9256 amu and its percentage abundance is 60.11%, let the mass of other isotope that is Ga-71 be X, the percentage abundance can be calculated as:
%Ga-71=100-60.11=39.89%
Atomic mass of an element is calculated by taking sum of atomic masses of its isotopes multiplied by their percentage abundance.
Thus, in this case:
Atomic mass= m(Ga-69)×%(Ga-69)+X×%(Ga-71)
From the periodic table, atomic mass of Ga is 69.723 amu.
Putting the values,

Thus,

Rearranging,

Therefore, mass of Ga-71 isotope is 70.9246 amu.
Answer:
Option (D)
Explanation:
Weathering is usually defined as the disintegration of rocks at the surface of the earth. This break down of rocks is mainly caused by the geological processes that occur on the earth's surface. This process results in the formation of sediments that are transported and deposited in a new environment.
This weathering process primarily takes place in three different ways such as-
- Physical weathering- Here, the rocks are broken down by the physical agents such as wind, water, ice.
- Chemical weathering- Here the rocks are broken down when interacts with the chemical containing water.
- Biological weathering- here, the rocks are broken down due to the activities done by organisms such as plants and animals.
In the given condition, Quincy can see a real example of rock weathering in the high mountainous region, as in the mountainous region the rocks are frequently weathered and eroded by the agents such as wind, water, and ice.
Thus, the correct answer is option (D).
Answer:
The two observations we made from viewing the solar system model are as follows as:
1). When we look at the sky we observe that the motions of all the planets and the stars are perfect circular movements with a good and high speed, but not in velocity because in velocity direction doesn't charges.
2). The sun is at the centre of our solar system and all the planets are equidistant to each other planets and also revolve around the sun.
Explanation:
I can give you some examples;
1) water
2) biomass
3)Soil
4) forest...
I hope this will help you
<u>36 ml of NaOh and</u><u> 464 ml</u><u> of </u><u>HCOOH</u><u> would be enough to form 500 ml of a buffer with the same pH as the buffer made with </u><u>benzoic acid </u><u>and NaOH.</u>
What is benzoic acid found in?
- Some natural sources of benzoic acid include: Fruits: Apricots, prunes, berries, cranberries, peaches, kiwi, bananas, watermelon, pineapple, oranges.
- Spices: Cinnamon, cloves, allspice, cayenne pepper, mustard seeds, thyme, turmeric, coriander.
Calculate the amount of moles in NaOH and benzoic acid. This calculation is done by multiplying molarity by volume.
Amount of moles of NaOH -2 × 0.025 = 0.05 mol
Amount of moles of benzoic acid 2 × 0.475 = 0.095 mol
In this case, we can calculate the pH produced by the buffer of these two reagents, as follows


We must repeat this calculation, with the values shown for HCOOH and NaOH. In this case, we can calculate as follows




Now we must solve the equation above. This will be done using the following values

With these values, we can calculate the volumes of NaOH and HCOOH needed to make the buffer.
NaOH volume
( 0.5 - 0.464)L
0.036L .................... 36ml
HCOOH volume
500 - 36 = 464mL
Learn more about benzoic acid
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