The mass will stay the same because of the conservation of mass
Answer:
check explaination
Explanation:
<u>Q. 4:</u>
a) 7 ml
b) 9 ml
c) volume of rock = volume of column (with rock in it) - volume of column (without rock)
= 9-7
= 2 ml
d) density = mass ÷ volume
therefore, mass = volume × density
= 2 × 3 => 6 g
<u>Q. 5:</u>
1st has the highest density
this is because, density = mass ÷ volume
as volume is constant , density is directly proportional to mass
as image 1 has more number of molecules, it's mass will be maximum.
therefore, 1st image will have maximum density
Answer:
Ozone layer protects from excessive amount of UV rays coming from the sun
Explanation:
Oxygen is converted into ozone by the following net balanced equation which requires UV light for initiation:
The process is extremely vital for human life. Let's think about the atmosphere. Ozone layer is also known as a protective layer, since it protects people from harmful ultraviolet radiation that is coming from the sun. In reality, we experience ultraviolet rays from the sun all the time, this is the reason why people get tanned (we wouldn't be able to achieve this with simply visible light). However, ozone layer controls the amount of the UV rays that reach Earth and decreases that number to the level where it becomes harmless to the people living on Earth.
Gold is a chemical element with symbol Au (from Latin: aurum) and atomic number 79, making it one of the higher atomic number elements that occur naturally. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal.
Pure gold is soft and is usually alloyed with other metals, such as silver, copper, platinum or palladium, to increase its strength. Gold alloys are used to make jewelry, decorative items, dental fillings and coins. The amount of gold in an alloy is measured with a unit called a karat.