All categories

2 years ago

Identify the blocks and groups of elements in the periodic table

Chemistry

1 answer:

djyliett [7]2 years ago

3 0

Explanation:

The periodic table is a table that arranges elements based on their atomic numbers into groups and periods.

The groups are the vertical arrangement of elements. All elements in a group share similar chemical properties because they have the same number of elements in their valence shell. The periodic table groups are:

Group Other names

1A or 1 Alkali metals

IIA or 2 Alkaline earth metals

IIIA or 3 Boron family

VIA or 6 Chalcogens

VIIA or 17 Halogens

O-18 Inert elements

IIIB-IIB Transition elements

There are 18 vertical columns divided into 8 tall groups or main groups which are 1A to O. The short groups or subgroups are from numerals 1B to VIII.

The periodic table can be divided into four blocks based on the type of sublevels their valence electrons occupy.

Group IA and IIA constitute the s-block
Group IIIA to O constitute the p-block
The transition elements makes up the d-block
The lanthanides and actinides makes up the f-block

Learn more:

Periodic table brainly.com/question/2014634

#learnwithBrainly

You might be interested in

A laboratory manual gave precise instructions for carrying out the reaction described by the chemical equation, C2H6O + O2 C2H4O

Alexxandr [17]

C2H6O + O2 ---> C2H4O2 + H2O

using the molar masses:-
24+ 6 + 16 g of C2H6O produces 24 + 4 + 32 g C2H4O2 (theoretical)
46 g produces 60g

60 g C2H4O2 is produced from 46g C2H6O
1g . .................................46/60 g
700g ................................. (46/60) * 700 Theoretically

But as the yield is only 7.5%

the required amount is ((46/60) * 700 ) / 0.075 = 7155.56 g

= 7.156 kg to nearest gram. Answer

8 0

2 years ago

A 5.0 g sample of calcium nitrate (Ca(NO3)2, M = 164) contaminated with silica (SiO2, M = 60.1) is found to contain 1.0 g calciu

zhenek [66]

Answer:

= 82%

Explanation:

Percentage purity is calculated by the formula;

% purity = (mass of pure chemical/total mass of sample) × 100

In this case;

1 mole of Ca(NO3)2 = 164 g

but; 164 g of Ca(NO3)2 = 40 g Ca

Therefore; mass of Ca(NO3)2 = 164 /40

= 4.1 g

Thus;

% purity of Ca(NO3)2 = (Mass of Ca(NO3)2/ mass of the sample)× 100

= (4.1 g/ 5 g) × 100

= 82%

4 0

2 years ago

Assume the weight of an average adult is 70. kg, and that 420. kJ of heat are evolved per mole of oxygen consumed as a result of

seraphim [82]

Answer:

The temperature difference of the body after 3 hours = 5.16 K

Explanation:

we know that the number of moles of O₂ inhaled are 0.02 mole/min⁻¹

or, 1.2 mole.h⁻¹

The average heat evolved by the oxidation of foodstuffs is then:

⇒ Q avg = $\frac{1.2 X 420 X 10^{3} }{70}$ = 7.2 kj.h⁻¹.Kg⁻¹

the heat produced after 3 h would be:

= 7.2 kj. h⁻¹.Kg⁻¹ x 3 h

= 21.6 kj. kg⁻¹

= 21.6 x 10³ j kg⁻¹

We know Qp = Cp x ΔT

Assume the heat capacity of the body is 4.18 J g⁻¹K⁻¹

⇒ ΔT = $\frac{Qp}{Cp}$

⇒ ΔT = $\frac{(21.6 X 10^{3} j.kg^{-1} ) }{(4.18 j k^{-1}g^{-1}) X (1000g.kg^{-1} )}$

⇒ ΔT = 5.16 K

6 0

2 years ago

If 6 g of element k combine with 17 g of element l, how many grams of element k combine with 85 g of element l?

Ede4ka [16]

Hope this helps you.

5 0

2 years ago

For the reaction below, Kp 5 1.16 at 800.8C. CaCO3(s) 34 CaO(s) 1 CO2(g) If a 20.0-g sample of CaCO3 is put into a 10.0-L contai

Elena L [17]

Answer:

The mass percentage of calcium carbonated reacted is 2.5%.

Explanation:

The reaction is:

$CaCO_{3}(s)--->CaO(s)+CO_{2}(g)$

Thus the Kp of the equilibrium will be:

Kp = partial pressure of carbon dioxide [as the other are solid]

Moles of calcium carbonate initially present = $\frac{mass}{molarmass}=\frac{20}{100}=0.2$

Let us apply ICE table to the equilibrium given:

$CaCO_{3}(s)--->CaO(s)+CO_{2}(g)$

Initial 0.2 0 0

Change -x +x +x

Equilibrium 0.2-x x x

Kp = partial pressure of carbon dioxide

Kp = Kc(RT)ⁿ

where n = difference in the number of moles of gaseous products and reactants

for given reaction n = 1

R = gas constant = 8.314 J /mol K

T = temperature = 800 ⁰C = 1073 K

Putting values

Kc = $\frac{Kp}{RT}=\frac{1.16}{8.314X1073}=1.3X10^{-4}$

Kc = $\frac{[CO_{2}][CaO]}{[CaCO_{3}]}= \frac{x^{2} }{(0.2-x)}=1.3X10^{-4}$

$1.3X10^{-4}(0.2-x)=x^{2}$

$x^{2} = 0.26X10^{-4}-1.3X10^{-4}x$

On calculating

x = 0.005

where x = the moles of calcium carbonate dissociated or reacted.

Percentage of the moles or mass reacted = $\frac{molesreacted X100}{initialmoles}=\frac{0.005X100}{0.2}=2.5$ %

7 0

2 years ago

Identify the blocks and groups of elements in the periodic table​

Identify the blocks and groups of elements in the periodic table