ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

How to Calculate Effective Nuclear Charge

Updated on June 15, 2015

Effective Nuclear Charge

Effective nuclear charge is the shielding effect of lower level electrons protecting valence electrons from the pull of the nucleus. The nucleus acts as a magnet to pull in electrons, but not all of them feel the full force of this magnetic attraction.

In short the lower the number, the less the electron in question feels the force of the nucleus pulling on it making it easier to be taken.

The formula is as follows:

Z_(eff) = Effective Nuclear Charge Z = Number of Protons S = Number of non valence electrons
Z_(eff) = Effective Nuclear Charge Z = Number of Protons S = Number of non valence electrons

Effective Nuclear Charge Practice

Use the formula to get the effective nuclear charge of Na and Br. Then compare the charges to see which one is more likely to give up electrons mathematically!

1. Na

First let's find out the atomic number of Na, it's 11, and use that as our Z. Next let's see how many electrons are in the valence shell. Since it's the first element on the 3rd row we know that has 1 in it's valence shell with 11 total. So we figure out how many of those electrons are NOT in the valence shell 1-11=10, so we plug in 10 as S and we solve!

2. Br

First we will find out the atomic number of Br, it's 35, this is Z. Next we find the number of electrons that are NOT in the valence shell. Based on it's position in the table we can count from the left to the right in the 4th row (making sure to skip the metals) we see it's the seventh element meaning it has 7 valence electrons so 35-7=28 so we use this as S.

Effective Nuclear Charge Conclusion

We can conclude then that based off of mathematically comparing Na (Zeff = +1) to Br (Zeff = +7) that Na's valence electron feels less positive force than Br's valence electrons.

Element
Atomic Number
Valence Electrons
Zeff
Li
3
1
+1
C
6
4
+4
Si
14
4
+4
Ca
20
2
+2
Sr
38
2
+2

A Few Effective Nuclear Charges

Consider the following table to ensure you understand how to calculate them without error. You will notice a pattern. Once you notice the pattern you will start to see yet another reason why the periodic table of elements is so ingeniously organized!

Comments

    0 of 8192 characters used
    Post Comment

    No comments yet.

    working

    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, hubpages.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://hubpages.com/privacy-policy#gdpr

    Show Details
    Necessary
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Features
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Marketing
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Statistics
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)