Molar mass HBr = 80.91 g/mol
number of moles:
mass of solute / molar mass
52 / 80.91 => 0.642 mols
Volume = 0.25 L
M = n / V
M = 0.642 / 0.25
M = 2.568 mol/L
hope this helps!
Answer:
There are 70 grams of KOH
Explanation:
First, we calculate the weight of 1 mol of KOH:
Weight 1 mol KOH: Weight K + Weight 0 + Weight H= 39g+ 1g+ 16g= 56 g/mol
1 mol-------56 g KOH
1,25 mol----x= (1,25 molx56 g KOH)/1 mol= <em>70 g KOH</em>
Answer:
1.5g/cm³
Explanation:
density=mass÷volume
mass= 1.5kg (<em>c</em><em>h</em><em>a</em><em>n</em><em>g</em><em>e</em><em> </em><em>i</em><em>n</em><em>t</em><em>o</em><em> </em><em>g</em>) = 1500g
volume of the cube = 10×10×10 = 1000cm³
density= divide 1500g÷1000cm = 1.5g/cm³
<h2>
Density= 1.5g/cm³</h2>
YOUR WELCOME!
Answer:
The repeating pattern of a mineral's particles form a solid called a <u>crystal</u>.
Explanation:
Answer:
Age of rock = 6.12 × 10³ years
Note: The question is incomplete.A similar but complete question is given below.
The half-life for the radioactive decay of carbon-14 to nitrogen-14 is 5.73 x 10^3 years. Suppose nuclear chemical analysis shows that there is 0.523mmol of nitrogen-14 for every 1.000 mmol of carbon-14 in a certain sample of rock.
Calculate the age of the rock. Round your answer to 2 significant digits.
Explanation:
The half-life of a radioactive material is the time taken for half the atoms in the atomic nucleus of a material to disintegrate.
The half-life for the radioactive decay of carbon-14 to nitrogen-14 is given as 5.73 x 10³ years. This means that given 1 mole of carbon-14 is present initially, after one half-life, 0.5 moles of carbon-14 would remain.
Number of millimoles of carbon-14 remaining = 1 - 0.523 = 0.477 mmol
Number of half-lives that the carbon-14 has undergone is determined as follows:
Amount remaining = (1/2)ⁿ
where nnis number of half-lives
0.5 mmol = one half-life
0.5 = (1/2)¹
O.477 = (1/2)ⁿ = (0.5)ⁿ
㏒₀.₅(0.477) = n
n = ㏒(0.477)/㏒(0.5)
n = 1.067938829
Age of the rock = number of half-lives × half-life
Age of rock = 1.067938829 × 5.73 × 10³ years
Age of rock = 6.12 × 10³ years