Answer:
Hi, There! I'm here to help!
Hydrogen is placed in group 1 in the modern periodic table.
This Statement Is True!
Explanation:
Hydrogen can form ionic compounds like other group I elements. Due to all of these similarities Hydrogen is placed in group I of the modern periodic table.
Answer:
Explanation:
The law of conservation of mass or principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as the system's mass cannot change, so the quantity can neither be added nor be removed.
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Answer:
Nitrogen
Explanation:
Nitrogen present 78% in the earth's atmosphere
Boyle's law of ideal gas: This law states that the volume of a gas is inversely proportional to its pressure at a constant temperature. Acc to this law we can write the relation of pressure and volume as:

That means:

From that equation we can calculate Volume of gas at a certain pressure:
P₁=Initial pressure
V₁=Initial volume
P₂=Final pressure
V₂= Final volume
Here P₁, initial pressure is given as 85.0 kPa
V₁, initial volume is given as 525 mL
P₂, final pressure is 65.0 kPa

so,
V_{2}=85\times 525\div 65
=686 mL
Volume of gas will be 686 mL.
Answer:
b. Loose clothing and jewelry is more likely to impede movement, or accidentally knock materials over, causing a spill or other accident.
Explanation:
Hello,
During the laboratories, a high dexterity is required, thus, such accessories, when you move or change your duty, could touch other materials or act out of your control resulting in spillages and constricting your proper movements and skills, that is why considering the lab safety policy, we must take those artifacts away from the chemistry lab.
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