I would say that you should wear a lab coat, safety goggles, and gloves
when the teacher says so - not everything in a lab is dangerous, so
there is no need to always wear these. But when the teacher says you
should - then you should.
Molar mass :
NaBr = 103 g/mol
Pb(NO3)2 = 331.20 g/mol
<span><span /><span>Balanced chemical equation :
</span></span>2 NaBr + 1 Pb(NO3)2 = 2 NaNO3 + 1 PbBr<span>2
</span><span>
2*103 g NaBr ------------> 1 * 331.20 g Pb(NO3)2
g NaBr -------------------> 311 g Pb(NO3)2
331.20 g = 2*103*311
331.20 g = 64066
mass ( NaBr ) = 64066 / 331.20
mass ( naBr) = 193,43 g of NaBr
hope this helps!.
</span>
Oxygen,hydrogen, and carbon
Answer: There are 
of gas are in a container with a volume of 9.55 mL at 35 °C and a pressure of 895 mmHg
Explanation:
According to ideal gas equation:
P = pressure of gas = 895 mm Hg= 1.18 atm (760 mm Hg= 1 atm)
V = Volume of gas = 9.55 ml = 0.00955 L (1 L=1000ml)
n = number of moles = ?
R = gas constant =
T =temperature =
Thus there are of gas are in a container with a volume of 9.55 mL at 35 °C and a pressure of 895 mmHg
