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3 years ago

S, selentum 83 has a half life

Chemistry

1 answer:

Sphinxa [80]3 years ago

4 0

The answer is 75 minutes.

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Consider the neutralization reaction that takes place when hydrochloric acid reacts with aqueous calcium hydroxide

Galina-37 [17]

2HCl + Ca(OH)2 -------> CaCl2 + 2H2O

5 0

3 years ago

1 Which scientist first said that "elements are made up of identical atoms

babunello [35]

Answer:

John Dalton

Explanation:

4 0

3 years ago

Iron metal reacts with elemental oxygen to form rust according to the unbalanced reaction, Fe(s) + O2(g) → Fe2O3(s),. What is th

pochemuha

Answer:

c. 3

Explanation:

The unbalanced reaction expression is given as:

Fe + O₂ → Fe₂O₃

To balance the expression gives the coefficient of oxygen.

Assign the coefficients a,b, c and use a mathematical approach to solve this problem:

aFe + bO₂ → cFe₂O₃

Conserving Fe: a = 2c

O: 2b = 3c

Now let c = 1, a = 2, b = $\frac{3}{2}$

Multiply through by 2,

a = 4, b = 3 and c = 2

4Fe + 3O₂ → 2Fe₂O₃

The coefficient of O₂ is 3

3 0

3 years ago

Which has a larger atomic radius, F or F-?

NeX [460]

F- due to the fact that it has one more electron.

Hope this helps and good luck :)

7 0

3 years ago

Read 2 more answers

In the reaction, Zn(s) + 2 HCl(aq) --> ZnCl2 (aq)+ H2(g), 25 grams of Zn are reacted with 17.5 g of HCl. How many grams of H2

Gennadij [26K]

Answer:

0.480 g of H₂ are produced, in the reaction.

Explanation:

This is the reaction:

Zn(s) + 2HCl → ZnCl₂ (aq) + H₂ (g)

We havethe mass of both reactants, so we must work with them to find out the limiting reactant and then, determine the amount of H₂ produced.

Let's convert the mass to moles ( mass / molar mass)

25 g / 65.41 g/mol = 0.382 moles Zn

17.5 g / 36.45 g/mol = 0.480 moles HCl

Ratio is 1:2, so 1 mol of Zn react with the double of moles of HCl.

0.382 moles of Zn would need the double of moles to react, so (0.382 .2) = 0.764 moles of HCl. → We only have 0.480 moles, so the acid is the limiting.

Now let's determine the moles of H₂ formed.

Ratio is 2:1, so If i take account the moles I have, I will produce the half of moles of my product.

0.480 moles / 2 = 0.240 moles of H₂ are produced.

To find out the mass, we must multiply mol . molar mass

0.240 mol . 2g/mol = 0.480 g

3 0

3 years ago