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2 years ago

Which of the following represents the raw materials of photosynthesis?

Chemistry

2 answers:

romanna [79]2 years ago

8 0

Answer:

Explanation:

B. Carbon dioxide(CO2)and water(H2O)

they represent the raw material of photosynthesis.

hope this helps you

cestrela7 [59]2 years ago

5 0

Answer is b
carbon dioxide and water

You might be interested in

The chemical force for which of the following ions is directed into the cell? The chemical force for which of the following ions

Over [174]

Answer:

Both sodium and calcium.

Explanation:

The membrane potential is maintained inside and outside of the cell due to the unequal distribution of the different ions. This membrane potential difference is important for the generation of action potential.

The resting membrane potential is around +30 mV. This is due to the presence of potassium ions. The sodium and calcium ions must enter in the cell to change this membrane potential and generates the action potential in the body.

Thus, the correct answer is option (3).

5 0

3 years ago

Which of the reactions are exothermic?

Nutka1998 [239]

Answer:

Reaction A, B, E and F are exothermic reactions.

Explanation:

Exothermic reactions are defined as the reactions in which energy of reactants is more than the energy of the products. In these reactions, energy is released by the system.

The total enthalpy of the reaction $(\Delta H)$ comes out to be negative.

Endothermic reactions are defined as the reactions in which energy of products is more than the energy of the reactants. In these reactions, energy is absorbed by the system.

The total enthalpy of the reaction $(\Delta H)$ comes out to be positive.

So, from the given option reaction which are exothermic are with negative value $(\Delta H)$ that enthalpy of reaction and those are:

1) $2Mg(s) + O_2( g )\rightarrow 2MgO (s)$ ,ΔH = -1203 kJ/mol

2) $NH_3 (g) + HCl (g)\rightarrow NH_4Cl (s)$ ,ΔH =-176 kJ/mol

3) $C(graphite) + O_2 (g)\rightarrow CO_2 (g)$ ,ΔH = -393.5 kJ/mol

4) $CH_4 (g) + 2O2 (g)\rightarrow CO_2 (g) + 2H_2O (l)$ ,ΔH =-891 kJ/mol

6 0

4 years ago

Cryolite, Na3AlF6(s), an ore used in the production of aluminum, can be synthesized using aluminum oxide. Balance the equation f

Korvikt [17]

Answer:

$55.2kgNa_{3}AlF_{6}$

Explanation:

1. First balance the equation for the synthesis of cryolite:

$Al_{2}O_{3}_{(s)}+6NaOH_{(l)}+12HF_{(g)}=2Na_{3}AlF_{6}+9H_{2}O_{(g)}$

2. Find the limiting reagent between the $Al_{2}O_{3},NaOH$ and $HF$

- First calculate the number of moles of each compound using its molar mass and the mass that reacted completely:

$13.4kgAl_{2}O_{3}*\frac{1molAl_{2}O_{3}}{101.96gAl_{2}O_{3}}*\frac{1000g}{1kg}=131molesAl_{2}O_{3}$

$55.4kgNaOH*\frac{1molNaOH}{40kgNaOH}*\frac{1000g}{1kg}=1385molesNaOH$ $55.4kgHF*\frac{1molHF}{20kgHF}*\frac{1000g}{1kg}=2770molesHF$

- Divide the number of moles obtained between the stoichiometric coefficient of each compound in the chemical reaction:

$Al_{2}O_{3}:\frac{131}{1}=131$

$NaOH:\frac{1385}{6}=231$

$HF:\frac{2770}{12}=231$

The $Al_{2}O_{3}$ is the limiting reagent because it has the smallest number.

3. Find the mass of cryolite produced:

$13.4kgAl_{2}O_{3}*\frac{1molAl_{2}O_{3}}{0.10196kgAl_{2}O_{3}}*\frac{2molesNa_{3}AlF_{6}}{1molAl_{2}O_{3}}*\frac{0.20994kgNa_{3}AlF_{6}}{1molNa_{3}AlF_{6}}=55.2kgNa_{3}AlF_{6}$

3 0

4 years ago

student in chemistry 150-02 weighed out 55.5g of octane c8h18 and allowed it to react with oxygen, o2 the product formed were ca

Tasya [4]

Answer:

C8H8 + 10O2 → 8CO2 + 4H2O

Explanation:

unbalanced reaction:

C8H8 + O2 → CO2 + H2O

balanced for semireactions:

(1) 16H2O + C8H8 → 8CO2 + 40H+

(2) 10(4H+ + O2 → 2H2O)

⇒ 40H+ + 10O2 → 20H2O

(1) + (2):

balanced reaction:

⇒ C8H8 + 10O2 → 8CO2 + 4H2O

8 - C - 8

20 - O2 - 20

8 - H - 8

3 0

4 years ago

why do solids keep their shape and volume why do liquids keep only volume and why do gases not keep either shape or volume

kodGreya [7K]

Solids always have definite shape and definite volume because their particles are packed together. Liquids have a definite volume but not definite shape, because their particles still kinda tight but able to move around, and gases don’t have a definite shape nor volume, because their particles are crazy and go everywhere

6 0

3 years ago