1. Hydrogen gas burns in air according to the equation below.

Why does the temperature of the water stay the same when it melts and boils?

krok68 [10]

The temperature stays the same when a solid changes to a liquid because energy is required to break the forces between particles of water therefore changing the state of matter and separating the particles away from each other.

When a liquid boils, the energy is needed by the particles to escape the surface of the liquid and boil. Instead of raising the temperature, the energy goes into the particles' kinetic energy store so it has enough speed to escape the surface of the liquid.

5 0

2 years ago

What reactions are responsible for the glow and heat from the sun? nuclear fission nuclear fusion chemical reactions atomic disi

Mamont248 [21]

Nuclear Fusion is the answer to the question who posted.

7 0

3 years ago

Read 2 more answers

A 3.50 g sample of an unknown compound containing only C , H , and O combusts in an oxygen‑rich environment. When the products h

statuscvo [17]

Explanation:

First, calculate the moles of $CO_{2}$ using ideal gas equation as follows.

PV = nRT

or, n = $\frac{PV}{RT}$

= $\frac{1 atm \times 4.41 ml}{0.0821 Latm/mol K \times 293 K}$ (as 1 bar = 1 atm (approx))

= 0.183 mol

As, Density = $\frac{mass}{volume}$

Hence, mass of water will be as follows.

Density = $\frac{mass}{volume}$

0.998 g/ml = $\frac{mass}{3.26 ml}$

mass = 3.25 g

Similarly, calculate the moles of water as follows.

No. of moles = $\frac{mass}{\text{molar mass}}$

= $\frac{3.25 g}{18.02 g/mol}$

= 0.180 mol

Moles of hydrogen = $0.180 \times 2$ = 0.36 mol

Now, mass of carbon will be as follows.

No. of moles = $\frac{mass}{\text{molar mass}}$

0.183 mol = $\frac{mass}{12 g/mol}$

= 2.19 g

Therefore, mass of oxygen will be as follows.

Mass of O = mass of sample - (mass of C + mass of H)

= 3.50 g - (2.19 g + 0.36 g)

= 0.95 g

Therefore, moles of oxygen will be as follows.

No. of moles = $\frac{mass}{\text{molar mass}}$

= $\frac{0.95 g}{16 g/mol}$

= 0.059 mol

Now, diving number of moles of each element of the compound by smallest no. of moles as follows.

C H O

No. of moles: 0.183 0.36 0.059

On dividing: 3.1 6.1 1

Therefore, empirical formula of the given compound is $C_{3}H_{6}O$ .

Thus, we can conclude that empirical formula of the given compound is $C_{3}H_{6}O$ .

6 0

3 years ago

Calcula el pH de estas soluciones: A-acido sulfúrico 0,0013 m B- hidróxido de socio 1,7 . 10 (-3) C- hidróxido de bario 2,2 . 10

Vladimir [108]

Answer:

ksüqkdbkavavsü hwkfülbjvvsb

4 0

2 years ago

What is the mass of 1.71 ✕ 1023 molecules of h2so4?

Anuta_ua [19.1K]

The equation for calculating a mass is as follows:

m=n×M

Molar mass (M) we can determine from Ar that can read in a periodical table, and a number of moles we can calculate from the available date for N:

n(H2SO4)=N/NA

n(H2SO4)= 1.7×10²³ / 6 × 10²³

n(H2SO4)= 0.3 mole

Now we can calculate a mass of H2SO4:

m(H2SO4) = n×M = 0.3 × 98 = 27.8 g

7 0

3 years ago