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3 years ago

Which of the following are considered pure substance??

Chemistry

1 answer:

Shkiper50 [21]3 years ago

7 0

Answer:

Explanation:

I’m 99.9% sure that it’s an element because it can’t be broken down any more than it already is.

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g Green plants use light from the Sun to drive photosynthesis. Photosynthesis is a chemical reaction in which water and carbon d

LenaWriter [7]

Answer:

6.49g

Explanation:

Let's consider the balanced reaction for photosynthesis.

6 CO₂ + 6 H₂O = C₆H₁₂O₆ + 6 O₂

We can establish the following relations:

1 mole of CO₂ has a mass of 44.01 g (MW 44.01)
The molar ratio of CO₂ to C₆H₁₂O₆ is 6:1.
1 mole of C₆H₁₂O₆ has a mass of 180.16 g/mol.

The mass of glucose produced by the reaction of 9.51 g of carbon dioxide is:

$9.51gCO_2 \times \frac{1molCO_2}{44.01gCO_2} \times \frac{1molGlucose}{6molCO_2} \times \frac{180.16gGlucose}{1molGlucose} = 6.49g Glucose$

6 0

3 years ago

Read 2 more answers

The density of table salt is 2.16 g/cm3. Detail the conversion into units of pounds per liter, and provide the density in lb/L.

Leona [35]

Answer:

density = 4.763pounds per liter

Explanation:

1g/cm³ = 2.205pounds per liter

2.16g/cm³ = (unknown)pounds per liter

(unknown)pounds per liter = 2.205 x 2.16 = 4.763

density = 4.763pounds per liter

4 0

3 years ago

When 50 ml of 1.000x10^-1m pb(no3)2 solution was added to 50 ml of 1.000x10^-1m nai solution?

podryga [215]

Balanced chemical reaction: Pb(NO₃)₂ (aq) + 2NaI(aq) → 2PbI₂(s) + 2NaNO₃(aq).

V(Pb(NO₃)₂) = 50 mL ÷ 1000 mL = 0.05 L, volume of solution.

c(Pb(NO₃)₂) = 0.1 mol/L; concentration of solution.

n(Pb(NO₃)₂) = c(Pb(NO₃)₂) · V(Pb(NO₃)₂).

n(Pb(NO₃)₂) = 0.1 mol/L · 0.05 L.

n(Pb(NO₃)₂) = 0.005 mol.

n(NaI) = c(NaI) · V(NaI).

n(NaI) = 0.1 mol/L · 0.05 L.

n(NaI) = 0.005 mol; amount of substance.

From chemical reaction: n(Pb(NO₃)₂) : n(NaI) = 1 : 2.

n(Pb(NO₃)₂) = 0.005 mol ÷ 2.

n(Pb(NO₃)₂) = 0.0025 mol; number of moles Pb(NO₃)₂ used.

n(NaI) = 0.005 mol; number of moles NaI used.

The limiting reagent is Pb(NO₃)₂.

n(PbI₂) = 0.005 mol.

m(PbI₂) = n(PbI₂) · M(PbI₂).

m(PbI₂) = 0.005 mol · 461 g/mol.

m(PbI₂) = 2.305 g; the theoretical yield of PbI₂.

3 0

3 years ago

Si 100 monedas tienen una masa total de 226.13g. Cual es la masa de una moneda

galben [10]

The mass of a coin : 2.2613 g

<h3>Further explanation </h3>

Algebraic expressions in mathematics are a combination of coefficients, numbers, variables, constants and arithmetic operations such as addition, subtraction, multiplication, and division.

The main composition of algebraic expressions are:

1. phrases

algebraic forms separated by arithmetic operations

consists of one phrase (monomial) to many phrases (polynomial)

2. variables

is a value that can be changed, can be in the form of letters, for example, x, y, a, b, etc.

3. constants

is a fixed value, can be a number

4. arithmetic operations ⇒ +, - , : , x

<em>If 100 coins have a total mass of 226.13g. What is the mass of a coin</em>

We can make this statement in the form of an algebraic equation :

100 coins=226.13 g

then the mass of a coin :

$\tt \dfrac{1}{100}\times 226.13~g=2.2613~g$

5 0

3 years ago

If you have 400 grams of a substance that decays with a half-life of 14 days, then how much will you have after 56 days? To help

alisha [4.7K]

Answer:

25 grams

Explanation:

You strat off with 400 grams of your substance. By day 14, half has dcayed and you only have 200 grams left. By day 28, there are 100 grams of the substance. On day 42, there are 50 grams left. Finally, on day 56, the substance has been through four half-lives and 25 grams remain.

3 0

3 years ago