A block of has a length of 7cm, a width of 4cm, and a height of 10cm. Its mass measures 840g. What is it's density?

Chemistry

1 answer:

andriy [413]2 years ago

3 0

Answer:

Explanation:

Density is

mass / volume = d

Mass:

840g

Volume:

7 cm x 4 cm x 10 cm = 280 cm^3

840g / 280 cm^3 = 3 g/cm^3

You might be interested in

write equations to show the chemical processes which occur when the first ionization and the second ionization energies of lithi

diamong [38]

Answer:

First ionization of lithium:

$\text{Li}\;(g)\to \text{Li}^{+} \; (g) + \text{e}^{-}$ .

Second ionization of lithium:

$\text{Li}^{+}\;(g) \to\text{Li}^{2+} \;(g) + \text{e}^{-}$ .

Explanation:

The ionization energy of an element is the energy required to remove the outermost electron from an atom or ion of the element in gaseous state. (Refer to your textbook for a more precise definition.) Some features of the equation:

Start with a gaseous atom (for the first ionization energy only) or a gaseous ion. Write the gaseous state symbol $(g)$ next to any atom or ion in the equation.
The product shall contain one gaseous ion and one electron. The charge on the ion shall be the same as the order of the ionization energy. For the second ionization energy, the ion shall carry a charge of +2.
Charge shall balance on the two sides of the equation.

First Ionization Energy of Li:

The products shall contain a gaseous ion with charge +1 $\text{Li}^{+}\;(g)$ as well as an electron $\text{e}^{-}$ .
Charge shall balance on the two sides. There's no net charge on the product side. Neither shall there be a charge on the reactant side. The only reactant shall be a lithium atom which is both gaseous and neutral: $\text{Li}\;(g)$ .

Hence the equation: $\text{Li}\;(g) \to \text{Li}^{+}\;(g) + \text{e}^{-}$ .

Second Ionization Energy of Li:

The product shall contain a gaseous ion with charge +2: $\text{Li}^{2+}\;(g)$ as well as an electron $\text{e}^{-}$ .
Charge shall balance on the two sides. What's the net charge on the product side? That shall also be the charge on the reactant side. What will be the reactant?

The equation for this process is $\text{Li}^{+} \; (g) \to \text{Li}^{2+}\;(g) + \text{e}^{-}$ .

5 0

3 years ago

Balance <br><br> _Mg + _HCL = _MgCl2 + H2

Pavel [41]

_Mg + _HCL = _MgCl2 + H2
Separate the terms on each side:

_Mg + _HCl = _MgCl2 + H2

Mg- 1 Mg-1

H-1 H-2

Cl-1 Cl-2

Mg is balanced on both sides so move on to the next (put a 1 in the space).

1Mg

There are two H's and two Cl's on the results side, so to balance the equation put a 2 as a coefficient for HCl and it'll all balance out.

2HCl

Balamced equation will be:

1Mg + 2HCL = 1MgCl2 + H2

5 0

3 years ago

Read 2 more answers

A sample of aluminum, which has a specific heat capacity of , is put into a calorimeter (see sketch at right) that contains of w

Oksanka [162]

Complete Question

A sample of aluminum, which has a specific heat capacity of 0.897 JB loc ! is put into a calorimeter (see sketch at right) that contains 200.0 g of water. The aluminum sample starts off at 85.6 °C and the temperature of the water starts off at 16.0 °C. When the temperature of the water stops changing it's 20.1 °C. The pressure remains constant at 1 atm. Calculate the mass of the aluminum sample.

Answer:

$M=58g$