Answers>Chemistry>A Level>Article

Explain why the first ionisation energy of barium is less than the first ionisation energy of calcium.

Barium is in the sixth period, Calcium is in the fourth. Therefore, Barium experiences more shielding, resulting in weaker attraction of the nucleus for outermost electrons.

JF
Answered by Joseph F. • Chemistry tutor

5363 Views

See similar Chemistry A Level tutors

Related Chemistry A Level answers

All answers ▸

Molecules of hydrogen chloride, HCl, and molecules of fluorine, F2, contain the same number of electrons. Hydrogen chloride boils at –85 °C and fluorine boils at –188 °C. Explain why there is a difference in the boiling points of HCl and F2.

Answered by Freddie G.

Give the IUPAC name of CH3CH2CH2CH2CH(OH)CN

Answered by Meg P.

A chemist mixes together 0.450 mol N2 with 0.450 mol H2 in a sealed container. The mixture is heated and allowed to reach equilibrium. At equilibrium, the mixture contains 0.400 mol N2 and the total pressure is 500 kPa. Calculate Kp.

Answered by Nayan G.

Which element, Na or Mg is likely to have the higher melting point? Give reasons for your choice

Answered by Monique P.

We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

Company Information

CareersBlogSubject answersBecome a tutorSchoolsSafeguarding policyFAQsUsing the Online Lesson SpaceTestimonials & pressSitemapTerms & ConditionsPrivacy PolicyGender Pay Gap Reporting

Popular Requests

Maths tutorChemistry tutorPhysics tutorBiology tutorEnglish tutorGCSE tutorsA level tutorsIB tutorsPhysics & Maths tutorsChemistry & Maths tutorsGCSE Maths tutors
CEOP logo
CLICK CEOP

Internet Safety

Sagepay logo

Payment Security

Cyber Essentials logo

Cyber

Essentials

MyTutor is part of the IXL family of brands:

IXL

Comprehensive K-12 personalized learning

Rosetta Stone

Immersive learning for 25 languages

Wyzant

Trusted tutors for 300 subjects

Education.com

35,000 worksheets, games, and lesson plans

Vocabulary.com

Adaptive learning for English vocabulary

Emmersion

Fast and accurate language certification

Thesaurus.com

Essential reference for synonyms and antonyms

Dictionary.com

Comprehensive resource for word definitions and usage

SpanishDictionary.com

Spanish-English dictionary, translator, and learning resources

FrenchDictionary.com

French-English dictionary, translator, and learning

Ingles.com

Diccionario ingles-espanol, traductor y sitio de apremdizaje

ABCya

Fun educational games for kids

© 2026 by IXL Learning