Answer:
H3PO4 is the formula for hydrophosphoric acid
Cathode rays are a stream of negatively charged particles or electrons in vacuum tubes. They were first seen by Johann Hittorf in 1869. They are named since they are emitted by electrode or cathode. In order to release the electrons, the electrons should first be detached from the atoms of the cathode.
Answer : The time required for decay is, 84 days.
Explanation :
Half-life of chromium-51 = 28 days
First we have to calculate the rate constant, we use the formula :



Now we have to calculate the time required for decay.
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = time taken by sample = ?
a = let initial activity of the sample = 100
a - x = amount left after decay process = 12.5
Now put all the given values in above equation, we get


Therefore, the time required for decay is, 84 days.
Answer:
the new pressure is 2.09 atm
Explanation:
you have to use gay lussac's law so the formula is
p1/t1 = p2/t2
and convert C to Kelvin k=C+273.15
1.72atm/294.15 = p2/358.15
solve for p2 by multiplying 358.15 on both sides
p2=2.09 atm
Answer:
250000 μL
Explanation:
If 1 L = 1000 mL
Then X L = 250 mL
X = (1 × 250) / 1000 = 0.25 L
Now we can calculate the number of microliters (μL) in 0.25 L:
if 1 μL = 10⁻⁶ L
then X μL = 0.25 L
X = (1 × 0.25) / 10⁻⁶ =250000 μL