1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
joja [24]
3 years ago
5

Identify the f-block element.

Chemistry
1 answer:
GaryK [48]3 years ago
3 0

Answer: E. none of these

Explanation: because the f-block element is n-2

You might be interested in
Limestone (CaCO3) is decomposed by heating to quicklime (CaO) and carbon dioxide. Calculate how many grams of quicklime can be p
Harman [31]

Answer: 2800 g

Explanation:

CaCO_3(s)\rightarrow CaO(s)+CO_2(g)

According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number 6.023\times 10^{23} of particles.

\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}

Given mass = 5 kg = 5000 g

\text{Number of moles}=\frac{5000g}{100g/mol}=50moles

1 mole of CaCO_3 produces = 1 mole of CaO

50 moles of CaCO_3 produces =\frac{1}{1}\times 50=50moles of CaO

Mass of CaO=moles\times {\text{Molar mass}}=50moles\times 56g/mole=2800g

2800 g of CaO is produced from 5.0 kg of limestone.

3 0
3 years ago
An atom that has a full valence electron shell can be found in which group?
kaheart [24]

Answer:

Noble Gasses

Explanation:

4 0
2 years ago
How can I identify easliy Amphoteric oxide from basic oxide​
never [62]

Answer:

A general guideline to determine if oxide is acidic, basic, or amphoteric is to use the periodic table. Typically, metals such as Ba form basic oxides (BaO), while nonmetals such as S form acidic oxides (SO3).

8 0
2 years ago
2. Calculate the number-average molecular weight of a random poly (isobutylene-isoprene) copolymer in which the fraction of isob
Phoenix [80]

Answer : The number-average molecular weight is, 97500 g/mol

Explanation :

First we have to calculate the molecular weight of isobutylene and isoprene.

The molecular formula of isobutylene and isoprene is, C_4H_8 and C_5H_8

Molecular weight of C_4H_8 = 4(12 g//mol) + 8(1 g/mol) = 56 g/mol

Molecular weight of C_5H_8 = 5(12 g//mol) + 8(1 g/mol) = 68 g/mol

Now we have to calculate the average repeat molecular weight.

Average repeat molecular weight = 0.25\times (56g/mol)+(1-0.25)\times (68g/mol)

Average repeat molecular weight = 65 g/mol

Now we have to calculate the number-average molecular weight.

Number-average molecular weight = Average repeat molecular weight × Degree of polymerization

Number-average molecular weight = (65 g/mol) × (1500)

Number-average molecular weight = 97500 g/mol

Thus, the number-average molecular weight is, 97500 g/mol

5 0
3 years ago
<img src="https://tex.z-dn.net/?f=%5Ccolor%20%7Bpink%7D%5Cboxed%7B%5Ccolorbox%7Bblack%7D%20%7B%20QUESTION%E2%99%A1%7D%7D" id="Te
zubka84 [21]

<em><u>Questi</u></em><em><u>on</u></em><em><u> </u></em><em><u>-</u></em>

<em><u>Expl</u></em><em><u>ain</u></em><em><u> </u></em><em><u>th</u></em><em><u>e</u></em><em><u> </u></em><em><u>classific</u></em><em><u>ation</u></em><em><u> </u></em><em><u>of</u></em><em><u> </u></em><em><u>hydro</u></em><em><u>carbons</u></em><em><u>?</u></em>

8 0
2 years ago
Other questions:
  • A _ reaction occurs when a substance usually containing carbon reacts with oxygen to produce energy in the form of light and hea
    12·1 answer
  • The reaction H2SO4 + 2 NaOH -&gt; Na2SO4 + 2H2O represents an acid-base tritration. The equivalence point occurs when 24.75 mL o
    10·1 answer
  • Which of Mendel's laws can be demonstrated by a dihybrid cross?
    13·1 answer
  • Need someone to answer this question as soon as possible
    10·1 answer
  • Calculate the molar mass of Co2
    13·1 answer
  • What elements are being reduced and oxidized in this chemical formula?
    14·1 answer
  • Wer the following questio What is meant by a solutio What is a saturated solutio Define: give an example.
    6·1 answer
  • the pressure on a 205 mL volume of gas is decreased from 985 mm hg to 615 mm hg while constant temperature is maintained, What i
    10·2 answers
  • A ____ has a mass of almost zero<br> A. Proton<br> B.Neutron<br> C. Electron<br> D.lon
    8·1 answer
  • Electrons and the Periodic Table
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!