How much °f of 35°C ? help me please

Determine the mass of MgCl2 needed to create a 100. ml solution with a concentration of 3.00 M.

kiruha [24]

Explanation:

$1000ml \: contain \: 3 \: moles \\ 100 \: ml \: will \: contain \: ( \frac{100 \times 3}{1000} ) \: moles \\ = 0.3 \: moles \\ RFM = 95 \\ 1 \: mole \: weighs \: 95 \: g \\ 0.3 \: moles \: weigh \: ( \frac{(0.3 \times 95)}{1} \: g \\ = 28.5 \: g \: of \: magnesium \: chloride$

5 0

2 years ago

Calculate the ph at of a solution of sodium hypochlorite . note that hypochlorous acid is a weak acid with a of . round your ans

loris [4]

The question is incomplete, here is the complete question:

Calculate the pH at 25°C of a 0.39 M solution of sodium hypochlorite NaClO. Note that hypochlorous acid HClO is a weak acid with a pKa of 7.50. Round your answer to 1 decimal place.

Answer: The pH of the solution is 10.4

Explanation:

We are given:

Molarity of sodium hypochlorite = 0.39 M

$pK_a$ of HClO = 7.50

We know that:

$pK_a=-\log K_a$

$K_a$ of HClO = $10^{-7.50}=3.16\times 10^{-8}$

To calculate the base dissociation constant for the given acid dissociation constant, we use the equation:

$K_w=K_b\times K_a$

where,

$K_w$ = Ionic product of water = $10^{-14}$

$K_a$ = Acid dissociation constant = $3.16\times 10^{-8}$

$K_b$ = Base dissociation constant

Putting values in above equation, we get:

$10^{-14}=3.16\times 10^{-8}\times K_b\\\\K_b=\frac{10^{-14}}{3.16\times 10^{-8}}=3.16\times 10^{-7}$

The chemical equation for the reaction of hypochlorite ion with water follows:

$ClO^-+H_2O\rightarrow HClO+OH^-$

Initial: 0.39

At eqllm: 0.39-x x x

The expression of $K_b$ for above equation follows:

$K_b=\frac{[HClO][OH^-]}{[ClO^-]}$

Putting values in above equation, we get:

$3.16\times 10^{-7}=\frac{x\times x}{(0.39-x)}\\\\x=-0.00035,0.00035$

Neglecting the negative value of 'x' because concentration cannot be negative

To calculate the pOH of the solution, we use the equation:

$pOH=-\log[OH^-]$

We are given:

$[OH^-]=0.00035M$

Putting values in above equation, we get:

$pOH=-\log (0.00035)=3.6$

To calculate pH of the solution, we use the equation:

$pH+pOH=14\\pH=14-3.6=10.4$

Hence, the pH of the solution is 10.4

3 0

2 years ago

If a sodium ion has 11 protons, 12 neutrons, and 11 electrons, what is the atomic mass of the atom?

iragen [17]

Answer:

23

Explanation:

we do not care about electrons, so 11 + 12 = 23

7 0

2 years ago

Which of the characteristics below best describes organic compounds

aleksandr82 [10.1K]

what are the options

4 0

2 years ago

Describe the region in model 1 where the highest concentration of hydrogen ion (h + ) is located

neonofarm [45]

THE HIGHEST CONCENTRATION OF HYDROGEN IONS IS LOCATED IN THE INTER-MEMBRANE SPACE. HYDROGEN IONS REACH THE INTER-MEMBRANE SPACE THROUGH PROTEIN CHANNELS EMBEDDED IN THE MITOCHONDRIAL MEMBRANE. THE MAIN FUNCTION OF INTER MEMBRANEIS OXIDATIVE PHOSPHORLATON. ENERGY IS REQUIRED TO MOVE THE HYDROGEN IONS ACROSS THE MEMBRANE BECAUSE THE HYDROGEN IONS ARE MOVING AGAINST THE CONCENTRATION GRADIENT. H+ GOES AGAINST THE CONCENTRATION GRADIENT THE USE OF THE GRADIENT TO DRIVE ATP SYNTHASE. HYDOGEN IONS DRIVE ATP SYNTHASE IN PHTOSYNTHESIS. THIS HAPPENS WHEN HYDROGEN IONS GET PUSHED ACROSS THE MEMBRANE CREATING A HIGH CONCENTRATION INSIDE THE THYLAKOID.

7 0

2 years ago

How much °f of 35°C ? help me please​

How much °f of 35°C ? help me please