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3 years ago

Why do elements in the same family generally have a similar properties ?

Chemistry

1 answer:

sattari [20]3 years ago

5 0

Answer:The elements have the same number of electrons in the outer ring so they react with the same substances

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If not managed properly, aquaculture can

Damm [24]

C. pollute water and damage aquatic ecosystems

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3 years ago

Aluminum reacts with sulfur gas to produce aluminum sulfide. a) What is the limiting reactant? What is the excess reagent? b) Ho

Sophie [7]

Answer:

a) Limiting: sulfur. Excess: aluminium.

b) 1.56g Al₂S₃.

c) 0.72g Al

Explanation:

Hello,

In this case, the initial mass of both aluminium and sulfur are missing, therefore, one could assume they are 1.00 g for each one. Thus, by considering the undergoing chemical reaction turns out:

$2Al(s)+3S_2(g)\rightarrow 2Al_2S_3(s)\\$

a) Thus, considering the assumed mass (which could be changed based on the one you are given), the limiting reagent is identified as shown below:

$n_S^{available}=1.00gS_2*\frac{1molS_2}{64gS_2} =0.0156molS_2\\n_S^{consumed\ by \ Al}=1.00gAl*\frac{1molAl}{27gAl}*\frac{3molS_2}{2molAl}=0.0556molS_2$

Thereby, since there 1.00g of aluminium will consume 0.0554 mol of sulfur but there are just 0.0156 mol available, the limiting reagent is sulfur and the excess reagent is aluminium.

b) By stoichiometry, the produced grams of aluminium sulfide are:

$m_{Al_2S_3}=0.0156molS_2*\frac{2molAl_2S_3}{3molS_2} *\frac{150gAl_2S_3}{1molAl_2S_3} =1.56gAl_2S_3$

c) The leftover is computed as follows:

$m_{Al}^{excess}=(0.0556-0.0156)molS_2*\frac{2molAl}{3molS_2}*\frac{27gAl}{1molAl} =0.72 gAl\\$

NOTE: Remember I assumed the quantities, they could change based on those you are given, so the results might be different, but the procedure is quite the same.

Best regards.

7 0

3 years ago

Dioxybenzone is a compound found in sunscreen, and only contains carbon, oxygen, and hydrogen. Analysis of the compound found th

Zina [86]

Chemical formula that shows the totalnumber and kinds of atoms in a molecule,but not their structural arrangement. Forexample, the molecular formula of aspirinis C9H8O4. Compare empirical formulastructural formula .
contains 4.92% hydrogen and 26.18% oxygen. The molar mass of the compound is 244.25 g/mol

6 0

3 years ago

Calculate the ph of a solution formed by mixing 200.0 ml of 0.30 m hclo with 300.0 ml of 0.20 m kclo. the ka for hclo is 2.9 × 1

velikii [3]

C(HClO) = 0,3 M.
V(HClO) = 200 mL = 0,2 L.
n(HClO) = c(HClO) · V(HClO).
n(HClO) = 0,06 mol.
c(KClO) = 0,2 M.
V(KClO) = 0,3 L.
n(KClO) = 0,06 mol.
V(buffer solution) = 0,2 L + 0,3 L = 0,5 L.
ck(HClO) = 0,06 mol ÷ 0,5 L = 0,12 M.
cs(KClO) = 0,06 mol ÷ 0,5 L = 0,12 M.
Ka(HClO) = 2,9·10⁻⁸.
This is buffer solution, so use Henderson–Hasselbalch equation:
pH = pKa + log(cs ÷ ck).
pH = -log(2,9·10⁻⁸) + log(0,12 M ÷ 0,12 M).
pH = 7,54 + 0.
pH = 7,54

6 0

3 years ago

3.0 x 108 m/s is the

Veseljchak [2.6K]

Answer:

Speed of light

Explanation:

The value 3.0 x 10⁸m/s is taken as the speed of light.

It is a constant.

It implies that light travels a distance of 3 x 10⁸ in just one second.
This value is for the speed of light in a vacuum when there are not particles obstructing its movement.
The speed of electromagnetic radiations in free space is also taken as the speed of light.

4 0

3 years ago