The mortar and pestle is most commonly used in chemical laboratories or in the kitchen. Its key function is to grind the material into smaller pieces, usually into its powdered form. It looks like that shown in the picture. The mortar is the bowl in which the material to be pounded is placed, and the pestle does the pounding.
Now, when you ask if it can only pound one at a time, my honest answer is, it depends. Depending on the size of your mortar, you could grind materials two or three at a time. But if you are concerned with contamination, then you do it one at a time, especially if you don't want them to get mixed up.
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Answer:</h3>
28.52 seconds
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Explanation:</h3>
Initial number of atoms of Nitrogen 12,000 atoms
Half-life = 7.13
Number of atoms after decay = 750 atoms
We are required to determine the time taken for the decay.
Note that half life is the time taken for a radioactive isotope to decay to a half of its original amount.
Using the formula;
Remaining amount = Initial amount × (1/2)^n , where n is the number of half lives
In our case;
750 atoms = 12,000 atoms × (1/2)^n
0.0625 = 0.5^n
n = log 0.0625 ÷ log 0.5
n = 4
But, 1 half life =7.13 seconds
Therefore;
Time taken = 7.13 seconds × 4
= 28.52 seconds
Therefore, the time taken for 12,000 atoms of nitrogen to decay to 750 atoms is 28.52 seconds
Answer:
B = mass, height
Gravitational potential energy is a function of the mass ans the height of an object.
Explanation:
The formula for gravitational potential energy is
GPE = mgh
m = mass in kilogram
g = acceleration due to gravity
h = height in meter above the ground
Formula:
GP.E = mgh
Consider the following example:
A crane lifts a 75kg mass a height of 8 m. Calculate the gravitational potential energy gained by the mass:
Formula:
GP.E = mgh
Now we will put the values in formula.
g = 9.8 m/s²
GP.E = 75 Kg × 9.8 m/s²× 8 m
GP.E = 5880 Kg.m²/s²
Kg.m²/s² = j
GP.E = 5880 j
First question. Applying ideal gas equation PV=nRT, P= 101.3 x 10³Pa = 1atm. therefore, 1 x 260 x 10^-3 = n x 0.082 x 294.( Temperature in kelvin=273+21). n = 0.01 moles. Volume of gas at STP= n x 22.4 = 0.01x22.4 = 0.224L. Hope this helps
It's the number of Protons of that atom..
