Summary BTEC applied science/forensincs, Unit 1: Trends revision notes
7 views 0 purchase
Course
Unit 1 - Principles and Applications of Science I
Institution
PEARSON (PEARSON)
This file contains my notes on trends taken in Unit 1 chemistry, they apply to both the BTECS applied science and forensics, as the unit is the same. Please leave a review! :3
Trends
Alkali metals
● Group 1
● Low densities
● React with water to form metal hydroxide
○ E.g Lithium + water = Lithium hydroxide
● React with non-metals to form ionic compounds
● Reactivity increases down the group
● First three (Li, Na and K) less dense than water
○ This causes them to float
● 2Na + 2H2O -> 2NaOH + H2
○ Sodium + water creating hydrogen gas and sodium hydroxide
○ Hydrogen gas can be tested for via squeaky pop test
Group 2, alkali metals
● Low density
● High melting and boiling point
● Forms metallic bonds (they are metals)
● Oxidation state +2
● Form colourless compounds
● Form ionic compounds
{ ● Tarnish in the air
● Reacts with oxygen to form metal oxide
○ When exposed to flame, it burns rapidly to produce white ionic oxide
○ Redox reaction
● Reacts with water to produce hydroxide gas
○ Mg reacts slowly in cold water but steadily with steam
○ Vigour of reaction increases down the group
● Very reactive, but less than group 1
○ Outer shell electrons are far from the nucleus
○ Ionisation energy decreases down the group
■ So reactivity increases
● Alkalinity increases down the group
● Solubility increases down the group
Group 7, halogens
● Diatomic (Never found naturally a single atom)
● Reacts with metals to form an ionic compound
○ Halogen becomes -1
● Reacts with non-metals to form a molecular compound
● Relative molecular mass increases down the group
● Melting and boiling point increase down the group
● Reactivity increases down the group
○ Outer shell is further from the nucleus making gaining electrons difficult
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Holly9587. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $3.89. You're not tied to anything after your purchase.