You are given 230 grams of a substance with a half-life of 0.75 years. How much will remain after 3 years?

A bulb is added to a circuit. When you place your hand near the bulb, it feels warm. The bulb in the circuit would most accurate

alex41 [277]

Answer:

C energy source

Explanation:

I got this right

8 0

2 years ago

Read 2 more answers

The strength of a covalent bond depends upon the size of the atoms and the bond order. In general short bonds are strong bonds.1

Oksana_A [137]

Answer:

Bond energy of (A) C≡C > (B) C=C

and, (C) C=N > (D) C-N

Explanation:

Bond energy refers to the amount of energy required to break a bond or the energy released when a bond is formed. Bond energy of a covalent bond suggests the bond strength of the chemical bond and depends on the bond length and bond order of the chemical bond.

The bond energy of a chemical bond increases with the bond order and decreases with the bond length. As, length of a bond decreases with increase in the bond order.

First pair: (A) C≡C (B) C=C

The bond order of C≡C - 3, the bond order of C=C - 2

Since the bond order: C≡C > C=C

Bond length: C≡C < C=C

Therefore, bond energy of (A) C≡C > (B) C=C

Second pair: (C) C=N (D) C-N

The bond order of C=N - 2, the bond order of C-N - 1

Since the bond order: C=N > C-N

Bond length: C=N < C-N

Therefore, bond energy of (C) C=N > (D) C-N

8 0

3 years ago

Arrange the processes of the water cycle in the correct order, starting with the heat from the Sun.

tensa zangetsu [6.8K]

There are four processes in water cycle. Starting from the heat from the sun is the process of evaporation.

Evaporation: In this process, light from the sun evaporate water from oceans, rivers, lakes, ice and soil into water vapor. Water vapor molecules combine to form clouds.

Condensation: In this process, water vapor from clouds cool down and turns back into liquid water in the form of water droplets. These water droplets stays in the air. Precipitation: In this process, water droplets they combine in the air, they become too heavy to stay in the air. Therefore, they fall in the form of rain, snow or other form.

Collection: In this process, water that falls as rain, snow or other form comes back in the ocean, lakes, river or any other water body. Water will also be absorbed by soil and will be collected as ground water.

;D

3 0

3 years ago

At the equilibrium point in the decomposition of phosphorus pentachloride to chlorine and phosphorus trichloride, the following

Hitman42 [59]

Answer: $K_{eq}$ for the reaction is 5.55

Explanation:

Equilibrium constant is the ratio of the concentration of products to the concentration of reactants each term raised to its stochiometric coefficients.

The given balanced equilibrium reaction is,

$PCl_5(g)\rightleftharpoons PCl_3(g)+Cl_2(g)$

At eqm. conc. (0.010) M (0.15) M (0.37) M

The expression for equilibrium constant for this reaction will be,

$K_c=\frac{[Cl_2]\times [PCl_3]}{[PCl_5]}$

Now put all the given values in this expression, we get :

$K_c=\frac{(0.37)\times (0.15)}{(0.010)}$

$K_c=5.55$

Thus the $K_{eq}$ for the reaction is 5.55

5 0

2 years ago

While camping you light a small campfire, initiating the combustion of wood to produce heat and

Ksju [112]

Answer:

A. It is exothermic

Explanation:

Combustion is a chemical reaction in which a substance combines with oxygen present in air to produce carbon (iv) oxide and water as well release heat and light energy.Combustion is an exothermic process.

An exothermic reaction releases energy in the form of heat to the surroundings. The energy required to break bonds in the reactants is less than the energy required to form new bonds in the products in an exothermic reaction.

From the given options;

A. It is exothermic is determinable since the reaction is a combustion reaction

B. The bond making energy is more than 600 kJ is not certain because the mass of the wood being burnt is not given. Also, wood is not composed of a specific element that would be taking part in the reaction, rather it is composed of various substances.

C. It is endothermic. is wrong because combustion of wood is exothermic.

D. The bond breaking energy is more than 600 kJ is not certain because the mass of the wood being burnt is not given. Also, wood is not composed of a specific element that would be taking part in the reaction, rather is composed of many substances.

5 0

3 years ago