The first thing you need to do with problem of this kind is to write the chemical equation. This would help you in calculations later. First, convert how many moles are there in 1.75g of carbon dioxide. Then, from the chemical equation you will know how many moles of sodium bicarbonate formed with 1 mole of carbon dioxide. Then convert the moles of sodium bicarbonate to grams using the molecular weight of the compound. You now have your answer.
Answer:
13 years
Explanation:
From;
0.693/t1/2 = 2.303/t log (No/N)
Where;
t1/12 = half-life of Cobalt-60 = 5.3 years
t = time taken = the unknown
No = mass of radioactive material originally present = 5.2 g
N = mass of radioactive material at time t = 0.95 g
Substituting values;
0.693/5.3 = 2.303/t log (5.2/0.95)
0.131 = 2.303/t(0.738)
0.131 = 1.6996/t
t = 1.6996/0.131
t = 12.97 years
t = 13 years(to the nearest whole number)
Answer:
Deben ser de igual número.
Explanation:
Using the periodic table to choose the element that matches each description include the following below:
<h3>What is a Periodic table?</h3>
This contains elements which are arranged according to the order of their atomic number in a tabular form. There are 18 groups which are the vertical columns present while there are 8 periods which are the horizontal rows present in the periodic table.
Example of an alkali metal is potassium while the non reactive ones include argon, neon etc. Examples of halogens include chlorine, iodine etc. are the ones which have seven electrons in their outer electron shells thereby just requiring one electron to achieve to obtain a stable octet configuration.
These are therefore the elements which match the descriptions provided in this case and is the most appropriate choice.
Read more about Periodic table here brainly.com/question/15987580
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