Science 1
10g of salt is added into 100g of water. what is the mass of the solution?
110g
what is the percentage of salt in seawater?
3.5%
what is the percentage of water in seawater?
96.5%
apart from sodium chloride? what other salts are present in seawater?
-magnesium chloride
-sodium sulfate
-calcium chloride
what is the color of the diamond when one nickel atom is present?
green
name the element that is present in pure diamond
carbon
is sand considered as solute? why?
no, because it cannot dissolve in solvent
10g of sugar was added into 50g of water. what is the mass of the solution?
60g
Give an example of solute
- sugar
- salt
Define the word solution.
A mixture of solvent and dissolve solute.
Name three properties of solutions
1.uniform, or homogeneous, throughout the mixture
2.It is stable and doesn't change over time or settle
3.The solute particles are so small they cannot be separated by filtering
4.The solute and solvent molecules cannot be distinguished by the naked eye
5.It does not scatter a beam of light, transparent.
What is the substance that can dissolved in water called?
solute
40g of salt was added into 35g of water. some of the salt did not dissolve in the water. Explain why.
Water is saturated
What is an example of solvent?
Water
◦Complete the sentence below.
◦
3.5% of the seawater is salt.
Of this 3.5%, about 68% is _____________ salt
Sodium chloride
5g of sugar was added into 55g of water. what is the mass of the solution?
60g
What is the symbol for magnesium cholride?
MgCl2
◦What is the percentage of water and salt in seawater?
Water – 96.5%
Salts – 3.5%
◦What is the element present in a pure diamond?
-Carbon atom only
◦What is the symbol for sodium chloride?
NaCl
◦What is the colour of the diamond when there is a present of Boron atom?
Blue
Calculate the percentage of silver in 850 silver ring.
-850/1000 x 100% = 85%
◦What is the name of element that makes the diamond to appear yellow?
-nitrogen
How many atom of nitrogen, nickel or hydrogen there is in a green diamond?
one
What is the percentage of gold atom in a 24 carat?
100%
what does it mean by pure gold bar?
gold bar that has only gold atom
◦Complete the sentence below.
Silver is usually marked with the number of parts per _____________.
-1000
What does it mean by the term ‘pure element’?
Every one of its atom is exactly the same and made of just one type of atom.]
◦What does it mean by 18 carat gold?
18 carat gold has 18 parts gold out of 24 gold. The rest are made up of other elements
What are the typical elements used in gold alloy?
Silver and copper.