.......... water is good for formation of bones and teeth, soft water or hard water?

The rate constant for the decomposition reaction of H2O2 is 3.66 × 10−3 s−1 at a particular temperature. What is the concentrati

Pepsi [2]

Answer: 3.72 M

Explanation:

Expression for rate law for first order kinetics is given by:

$t=\frac{2.303}{k}\log\frac{a}{a-x}$

where,

k = rate constant = $3.66\times 10^{-3}s^{-1}$

t = age of sample = 15.0 minutes

a = let initial amount of the reactant = 10.0 M

a - x = amount left after decay process = ?

$15.0\times 60s=\frac{2.303}{3.66\times 10^{-3}}\log\frac{10.0}{(a-x)}$

$\log\frac{100}{(a-x)}=1.43$

$\frac{100}{(a-x)}=26.9$

$(a-x)=3.72M$

The concentration of $H_2O_2$ in a solution after 15.0 minutes have passed is 3.72 M

7 0

3 years ago

A gas occupies the volume of 215ml at 15C and 86.4kPa?

kherson [118]

Answer:

About 0.1738 liters

Explanation:

Using the formula PV=nRT, where p represents pressure in atmospheres, v represents volume in liters, n represents the number of moles of ideal gas, R represents the ideal gas constant, and T represents the temperature in kelvin, you can solve this problem. But first, you need to convert to the proper units. 215ml=0.215L, 86.4kPa is about 0.8527 atmospheres, and 15C is 288K. Plugging this into the equation, you get:

$0.8527\cdot 0.215=n \cdot 0.0821 \cdot 288\\n\approx 7.754 \cdot 10^{-3}$

Now that you know the number of moles of gas, you can plug back into the equation with STP conditions:

$1V=7.754 \cdot 10^{-3} \cdot 0.0821 \cdot 273\\V\approx 0.1738L$

Hope this helps!

3 0

4 years ago

What do you expect will occur as air masses move over cold locations? Hot locations? How does this movement of air masses affect

Maksim231197 [3]

Answer:

Explanation:

When air masses will move over cold location then bottom layer of air cools and become more dense. Due to its high density it is trapped near the ground then it flow towards the equator.

When it moves over hot location then bottom layer gets hot and lighter. Then it moves towards poles.

It changes the temperature and humidity of the climate. making hoter region coll and cooler region a bit hot.

3 0

3 years ago

How many moles are found in 10.5 g of Pb?

deff fn [24]

Answer:

Number of moles = 0.05 mol

Explanation:

Given data:

Mass of Pb = 10.5 g

Number of moles of Pb = ?

Solution:

Formula:

Number of moles = mass/molar mass

Molar mass of Pb is 207.2 g/mol.

Now we will put the values in formula.

Number of moles = 10.5 g/207.2 g/mol

Number of moles = 0.05 mol

6 0

3 years ago

In ionic bonding, during the transfer of electrons between two neutrally charged atoms, one electron moves from one atom to anot

forsale [732]

The given question is incomplete . The complete question is :

In ionic bonding, during the transfer of electrons between two neutrally charged atoms, one electron moves from one atom to another. What are the new relative charges between the two atoms?

a. The giving atom and receiving atom are both negatively charged

b. The giving atom is now positively charged and the receiving atom is now negatively charged.

c. The giving and receiving atom are both positively charged

d. The giving atom is now negatively charged and the receiving atom is now positively charged.

Answer: The giving atom is now positively charged and the receiving atom is now negatively charged.

Explanation:

Ionic compounds are formed by transference of electrons between metals and non metals. The bond formed between a metal and a non-metal is always ionic in nature.

For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.

Thus when one electron moves from one atom to another, the metal acquires a positive charge and the non metal acquires negative charge.

For example: $NaCl$ is formed by transfer of one electron from sodium to chlorine , thus forming $Na^+$ and $Cl^-$

3 0

3 years ago

.......... water is good for formation of bones and teeth, soft water or hard water? ​

.......... water is good for formation of bones and teeth, soft water or hard water?