Mass of lead (II) chromate is 51 g. The molecular formula is
and its molar mass is 323.2 g/mol
Number of moles can be calculated using the following formula:

Here, m is mass and M is molar mass.
Putting the values,

Therefore, number of moles of lead (II) chromate will be 0.1578 mol.
The element used in advertising signs is neon.
S, sulfur does not have a noble gas electron.
0.208 is the specific heat capacity of the metal.
Explanation:
Given:
mass (m) = 63.5 grams 0R 0.0635 kg
Heat absorbed (q) = 355 Joules
Δ T (change in temperature) = 4.56 degrees or 273.15+4.56 = 268.59 K
cp (specific heat capacity) = ?
the formula used for heat absorbed and to calculate specific heat capacity of a substance will be calculated by using the equation:
q = mc Δ T
c = 
c = 
= 0.208 J/gm K
specific heat capacity of 0.208 J/gm K
The specific heat capacity is defined as the heat required to raise the temperature of a substance which is 1 gram. The temperature is in Kelvin and energy required is in joules.
Hey there!:
From the given data ;
Reaction volume = 1 mL , enzyme content = 10 ug ( 5 ug in 2 mg/mL )
Enzyme mol Wt = 45,000 , therefore [E]t is 10 ug/mL , this need to be express as "M" So:
[E]t in molar = g/L * mol/g
[E]t = 0.01 g/L * 1 / 45,000
[E]t = 2.22*10⁻⁷
Vmax = 0.758 umole/min/ per mL
= 758 mmole/L/min
=758000 mole/L/min => 758000 M
Therefore :
Kcat = Vmax/ [E]t
Kcat = 758000 / 2.2*10⁻⁷ M
Kcat = 3.41441 *10¹² / min
Kcat = 3.41441*10¹² / 60 per sec
Kcat = 5.7*10¹⁰ s⁻¹
Hence kcat of xyzase is 5.7*10¹⁰ s⁻¹
Hope that helps!