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4 years ago

(50 POINTS!)

Chemistry

2 answers:

aleksandrvk [35]4 years ago

7 0

Answer:

Can I get my 50 points now?

Explanation:

The helium is formed during the natural radioactive decay of elements such as uranium and thorium. These heavy elements were formed before the earth but they are not stable and very slowly, they decay. One mode of decay for uranium is to emit an alpha-particle.

nasty-shy [4]4 years ago

4 0

The sun converts hydrogen atoms into helium.

You might be interested in

What does it mean to have high density?

lord [1]

Density describes how compact or concentrated something is. For example, suppose you have two boxes, one large and one small. ... That means the small box has a higher density than the large box. Density also tells how concentrated or crowded something is.

4 0

3 years ago

La columna de la izquierda corresponde a los tipos de sales y la columna derecha a los tipos de fórmula que presentan. Relaciona

Galina-37 [17]

Answer:

1. Hidracidas a. MX

2 Acidas c. MHXO

3. Oxacidas b. MXO

4. Basicas d. M(OH)X

Explanation:

¡Hola!

En este caso, de acuerdo con el concepto de sal, la cual está generalmente dada por la presencia de al menos un metal y un no metal, es posible encontrar cuatro tipos de estas; hidrácidas, oxácidas, básicas y ácidas, en las que las primeras dos son neutras pero la segunda tiene presencia de oxígeno, la tercera tiene iones hidróxido adicionales y la cuarta iones hidrógeno de más.

Debido a la anterior, es posible relacionar cada pareja de la siguiente manera:

1. Hidracidas a. MX

2 Acidas c. MHXO

3. Oxacidas b. MXO

4. Basicas d. M(OH)XO

En las que M se refiere a un metal, X a un no metal, H a hidrógeno y O a oxígeno.

¡Saludos!

3 0

3 years ago

5. In an oxyacetylene welding torch, acetylene (C2H2) burns in pure oxygen with a very hot flame. The reaction is: 2 C2H2 + 5 O2

gulaghasi [49]

11.375 g ethylene is consumed if 35.0 grams of oxygen is allowed to react and 7.875 ml of water will be produced when the 35.0 grams of oxygen is allowed to react.

<h3>What are moles?</h3>

A mole is defined as 6.02214076 × $10^{23}$ of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.

According to the chemical equation for the combustion of ethylene, 5

moles of oxygen are required to react with 2 moles of ethylene, hence

$m_{_C_2_H_2}$ $= 35gX \frac{1 mol}{(2 \;X\; 16)g } X \frac{2 mol}{(5\;mol )} X \frac{26g}{1 mol }$

$m_{_C_2_H_2} = 11.375 g$

Similarly, 5 moles of oxygen are required as a reactant to produce 2 moles of water, thus

$m_{_H_2_O} = 35gX \frac{1 mol}{(2 \;X\; 16)g } X \frac{2 mol}{(5\;mol )} X \frac{18g}{1 mol }$

$m_{_H_2_O} = 7.875 g$

Given that the density of water is $1.0g ml^{-1}$ , therefore

$Density = \frac{Mass \;of \;water}{Volume \;of \;water}$

$Volume \;of \;water = \frac{7.875}{1.0 g ml^{-1}}$

The volume of water = 7.875 ml

Learn more about moles here:

brainly.com/question/8455949

#SPJ1

5 0

2 years ago

Read 2 more answers

Why do scientists use models?

Travka [436]

Answer:

Models make some things easier to understand.

Measurements can be made only on models.

Models help scientists visualize things they can’t see.

Models are perfectly accurate representations of objects.

Scientists can analyze models to make predictions.

Explanation:

Mark as brainliest......

6 0

4 years ago

How many moles of solute particles are present in 1 ml of aqueous 0.020 m (nh4)2co3?

Dima020 [189]

Vs = 1.0 mL = 0.001 L
c((NH4)2CO3) = <span>0.02 M
n(</span>(NH4)2CO3) = ?

For the purpose, here we will use the next equation:

c=n/V ⇒ n=cxV

n((NH4)2CO3) = 0.02M x 0.001L

n((NH4)2CO3) = 2x10⁻⁵ mole of (NH4)2CO3 is presented in the solution

6 0

3 years ago