# Author: univerkov

## Classification of organisms

Scientists suggest that more than 10 million species of living organisms currently live on the planet. Therefore, it is very important to classify them, that is, to distribute

## Write down the equations of 3-4 exchange reactions resulting in the formation of iron (II) sulfate.

FeO+H₂SO₄=FeSO₄+H₂O Fe(OH)₂+H₂SO₄=FeSO₄+H₂O Fe+H₂SO₄=FeSO₄+H₂↑

## The perimeter of an isosceles triangle is 20.4 m. Find its sides if the base is 3 m less than the lateral side.

Let’s designate the sides of the triangle (a and b) as x, then the base (c) will be equal to x – 3. Through the perimeter, we find

## What about opposite angles and sides of a parallelogram?

Let a parallelogram ABCD be given. Pairs of sides AB and CD, AD and BC are parallel to each other and equal to each other. Pairs of angles

## How much gasoline is consumed in an internal combustion engine that drives a pump that draws 4 tons of

How much gasoline is consumed in an internal combustion engine that drives a pump that draws 4 tons of oil from a depth of 1,500 meters? Motor efficiency

## How much heat must be imparted to a piece of ice with a mass of 50 g at 0 ℃

How much heat must be imparted to a piece of ice with a mass of 50 g at 0 ℃ in order to melt it and heat the

## How many moles of calcium oxide are formed when 8 g of calcium containing 30% impurities are burned in oxygen?

Given: m tech. (Ca) = 8 g ω approx. = 30% Find: n (CaO) -? Solution: 1) 2Ca + O2 => 2CaO; 2) ω (Ca) = 100% –

## What volume of hydrogen will be released during the interaction of 2.7 g of 25% hydrochloric acid with the amount

What volume of hydrogen will be released during the interaction of 2.7 g of 25% hydrochloric acid with the amount of aluminum substance required for the reaction? How