Answer:
Density, d = 1.779 g/cm³
Explanation:
The density of a material is given by its mass per unit volume.
Here, height of a piece of magnesium cylinder, h = 5.62 cm
Its diameter, d = 1.34 cm
Radius = 0.67 cm
Volume of he cylinder,
So, the density of the sample is 1.779 g/cm³.
The balanced equation :
8Al + 3Fe₃O₄→ 4Al₂O₃ + 9Fe
You just have to look for which element is in bold because the question is not clear
<h3>Further explanation</h3>
Equalization of chemical reaction equations can be done using variables. Steps in equalizing the reaction equation:
1. gives a coefficient on substances involved in the equation of reaction such as a, b, or c etc.
2. make an equation based on the similarity of the number of atoms where the number of atoms = coefficient × index between reactant and product
3. Select the coefficient of the substance with the most complex chemical formula equal to 1
Reaction
Al + Fe₃O₄→ Al₂O₃ + Fe
give a coefficient
aAl + Fe₃O₄→ bAl₂O₃ + cFe
O, left=4, right=3b⇒3b=4⇒b=4/3
Al, left=a, right=2b⇒a=2b⇒a=2.4/3⇒a=8/3
Fe, left=3, right=c⇒c=3
The equation becomes :
8/3Al + Fe₃O₄→ 4/3Al₂O₃ + 3Fe x3
8Al + 3Fe₃O₄→ 4Al₂O₃ + 9Fe
Answer:
C. to explore the composition of Mars
Explanation:
Initially, in 2019, an unmanned mission is planned to orbit the moon. The spacecraft would flyby the moon. In 2020's, the Exploration Mission 2 would be a manned mission on the same path around the moon. This would be the base for future goal of collecting samples from mars. In later of 2020's unmanned spacecraft would be sent to mars and a robot would collect the samples from the Martian surface. In 2030's, a crew would be sent to Mars.
<span>Chemically speaking, rust is a base and any acid will remove it. The choice of acid is going to be the thing to consider, since acid + base = salt and water. Phosphoric acid left a residue because the salt Iron phosphate is insoluble in water. Iron's soluble salts include the chloride, the sulfate and the nitrate. Industrially speaking, you need to "pickle" your iron. Pickling is a process in which dilute sulfuric acid is used to remove any surface corrosion prior to either painting or plating an iron surface. Sulfuric acid is ordinary battery acid and the salt Iron sulfate is not toxic. Sulfuric acid is one of the most common acids used (besides hydrochloric acid). The dilute kind is not terribly corrosive but concentrated sulfuric acid is a thick, syrupy liquid which can cause some nasty chemical burns if allowed to remain on the skin. It also heats up quite a lot when water is added, so this is an "Acid to water not water to acid" situation. The other choice is Hydrochloric acid, known as muriatic acid. The 20% concentrate is available in nearly any hardware store. It isn't as corrosive as concentrated sulfuric acid, but it has a burning, acrid stench, so never use the concentrate without adequate ventilation. It is ordinarily used to remove hard water deposits (boiler scale) but does a good on on rust as well. Concentrated Iron chloride isn't entirely inert but lots of rinsing will turn it back into harmless rust/sludge, especially if the rince water is naturally hard. Nitric acid will remove corrosion from anything, but it is extremely corrosive, smells worse then Hydrochloric acid and isn't easy to get, since it can be used to create some powerful explosives</span>
The correct answer would have to be true
