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3 years ago

Why does an ice cube melt when you hold it in your hand?

Chemistry

2 answers:

Ede4ka [16]3 years ago

8 0

heat is transferred from your hand to the ice cube

aniked [119]3 years ago

5 0

Answer:

Heat is transferred from your hand to the ice cube.

You might be interested in

Match the following words.

azamat

Answer:

1. active site

2. substrate.

3. activity

4. cofactor

5. complex

6. coenzyme.

Explanation:

1. A substrate binds to an enzyme at the active site where the reaction occurs.

2. In a catalyzed reaction, a reactant is often called a substrate.

3 activity is a measure of how fast an enzyme can convert the reagent to the product.

4. An inorganic substance necessary for the function of some enzymes is called a cofactor.

5. When properly aligned, the enzyme and substrate form an enzyme-substrate (ES) complex.

6. A small organic molecule necessary for the function of some enzymes is called a coenzyme.

7 0

3 years ago

A 8 kg cat is running 4 m/s. How much kinetic energy does it have

Debora [2.8K]

<span>KE = 1/2mv^2
KE = 1/2(8)4 m/s^2
KE = 4*4
KE = 16 Joules

Kinetic energy would equal 16 J </span>

8 0

3 years ago

Given that a 12.00 g milk chocolate bar contains 8.000 g of sugar, calculate the percentage of sugar present in 12.00 g of milk

neonofarm [45]

So in order for us to know the percentage of sugar present in a 12.00 g of milk chocolate, what we are going to do is that, we just have to divide 8 by 12 and multiply in by 100 and we get 66.67. Therefore, the percentage of sugar present in 12.00 g of milk chocolate bar is 66.67%. Hope this answers your question. Have a great day!

5 0

3 years ago

Read 2 more answers

1. The solubility of lead(II) chloride at some high temperature is 3.1 x 10-2 M. Find the Ksp of PbCl2 at this temperature.

solniwko [45]

Answer:

1) The solubility product of the lead(II) chloride is $1.2\times 10^{-4}$ .

2) The solubility of the aluminium hydroxide is $1.6\times 10^{-10} M$ .

3)The given statement is false.

Explanation:

Solubility of lead chloride = $S=3.1\times 10^-2M$

$PbCl_2(aq)\rightleftharpoons Pb^{2+}(aq)+2Cl^-(aq)$

S 2S

The solubility product of the lead(II) chloride = $K_{sp}$

$K_{sp}=[Pb^{2+}][Cl^-]^2$

$K_{sp}=S\times (2S)^2=4S^3=4\times (3.1\times 10^{-2})^3=1.2\times 10^{-4}$

The solubility product of the lead(II) chloride is $1.2\times 10^{-4}$ .

Concentration of aluminium nitrate = 0.000010 M

Concentration of aluminum ion = $1\timed 0.000010 M=0.000010 M$

Solubility of aluminium hydroxide in aluminum nitrate solution = $S$

$Al(OH)_3(aq)\rightleftharpoons Al^{3+}(aq)+3OH^-(aq)$

S 3S

The solubility product of the aluminium nitrate = $K_{sp}=1.0\times 10^{-33}$

$K_{sp}=[Al^{3+}][OH^-]^3$

$1.0\times 10^{-33}=(0.000010+S)\times (3S)^3$

$S=1.6\times 10^{-10} M$

The solubility of the aluminium hydroxide is $1.6\times 10^{-10} M$ .

$Molarity=\frac{Moles}{Volume (L)}$

Mass of NaCl= 3.5 mg = 0.0035 g

1 mg = 0.001 g

Moles of NaCl = $\frac{0.0035 g}{58.5 g/mol}=6.0\times 10^{-5} mol$

Volume of the solution = 0.250 L

$[NaCl]=\frac{6.0\times 10^{-5} mol}{0.250 L}=0.00024 M$

1 mole of NaCl gives 1 mole of sodium ion and 1 mole of chloride ions.

$[Cl^-]=[NaCl]=0.00024 M$

Moles of lead (II) nitrate = n

Volume of the solution = 0.250 L

Molarity lead(II) nitrate = 0.12 M

$n=0.12 M]\times 0.250 L=0.030 mol$

1 mole of lead nitrate gives 1 mole of lead (II) ion and 2 moles of nitrate ions.

$[Pb^{2+}]=[Pb(NO_2)_3]=0.030 M$

$PbCl_2(aq)\rightleftharpoons Pb^{2+}(aq)+2Cl^-(aq)$

Solubility of lead(II) chloride = $K_{sp}=1.2\times 10^{-4}$

Ionic product of the lead chloride in solution :

$Q_i=[Pb^{2+}][Cl^-]^2=0.030 M\times (0.00024 M)^2=1.7\times 10^{-9}$

$Q_i$ ( no precipitation)

The given statement is false.

3 0

4 years ago

What is the main factor that prevents the growth of tropical plants in northern part of the United States ?

slamgirl [31]

The main factor that prevents the growth of tropical plants in the northern part of the United States is the climate. The tropical plants require specific conditions to grow and flourish, including warm climate throughout the year, higher precipitation, lots of sunlight. This conditions are lacking in the northern part of the United States where we have smaller amount of sunlight, mostly cloudy sky, and the winters are extremely cold and with lots of snow, and this will contribute to the dying of a tropical plant.

6 0

3 years ago