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- Factorize completely; a2-15ab +36b2
Factorize completely; a2-15ab +36b2
Date posted: February 23, 2019
- 1.60g of an oxide of Magnesium contain 0.84g by mass of Magnesium. Determine its empirical formula(Mg = 24.0, 16.0)
1.60g of an oxide of Magnesium contain 0.84g by mass of Magnesium. Determine its empirical formula(Mg = 24.0, 16.0)
Date posted: February 25, 2019
- Solve for the following
27x +33x+1 =108
Solve for the following
27x +33x+1 =108
Date posted: February 25, 2019
- Solve the simultaneous equation
3x – 4y =10
X + 3y = -1
Solve the simultaneous equation
3x – 4y =10
X + 3y = -1
Date posted: February 26, 2019
- Find the value of x in
(logx)2 -15(logx) + 56 = 0
Find the value of x in
(logx)2 -15(logx) + 56 = 0
Date posted: February 26, 2019
- Find the equation of a line passing through (4, -3) and parallel to the line whose equation is
4y – 3x = 8.
Find the equation of a line passing through (4, -3) and parallel to the line whose equation is
4y – 3x = 8.
Date posted: February 26, 2019
- Simplify the equation below
Simplify the equation below
![eq126220191201.png](https://www.kenyaplex.com/videolessons/uploads/eq126220191201.png)
Date posted: February 26, 2019
- Solve for X in the equation below 32(x - 3) ÷ 8(x - 4) = 64 ÷ 2x
Solve for X in the equation below
32(x - 3) ÷ 8(x - 4) = 64 ÷ 2x
Date posted: February 26, 2019
- Given that a=2, b=1, and c=3, find the value of
Given that a=2, b=1, and c=3, find the value of
![frac126220191221.png](https://www.kenyaplex.com/videolessons/uploads/frac126220191221.png)
Date posted: February 26, 2019
- Arrange the following fractions in descending order.
Arrange the following fractions in descending order.
![frac226220191232.png](https://www.kenyaplex.com/videolessons/uploads/frac226220191232.png)
Date posted: February 26, 2019
- The cost of a pen is sh.X and that of a pencil is sh. 4 less than that of a pen. Find the combined cost of 4 pens and 5 pencils.
The cost of a pen is sh.X and that of a pencil is sh. 4 less than that of a pen. Find the combined cost of 4 pens and 5 pencils.
Date posted: February 26, 2019
- Factorize: 6x2 -13x + 6
Factorize: 6x2 -13x + 6
Date posted: February 26, 2019
- During heating of a hydrated copper (II)sulphate crystals, the following readings were obtained:
Mass of evaporating dish =300.0g, Mass of evaporating dish + hydrated salt = 305.0g, Mass of evaporating dish + anhydrous salt = 303.2g
During heating of a hydrated copper (II)sulphate crystals, the following readings were obtained:
Mass of evaporating dish =300.0g, Mass of evaporating dish + hydrated salt = 305.0g, Mass of evaporating dish + anhydrous salt = 303.2g
Calculate the number of water of crystallization molecules in hydrated copper (II)sulphate.(Cu =64.5, S = 32.0,O=16.0, H = 1.0)
Date posted: February 26, 2019
- An element Q consists of 3 isotopes of mass 28, 29, 30 and percentage abundance of 92.2%, 4.7%, 3.1% respectively. Determine the relative atomic mass of the element?
An element Q consists of 3 isotopes of mass 28, 29, 30 and percentage abundance of 92.2%, 4.7%, 3.1% respectively. Determine the relative atomic mass of the element?
Date posted: February 26, 2019
- An element N forms an ion N2. This ion contains 18 electrons:
a) State the period and the group of the periodic table that element N belongs.
An element N forms an ion N2. This ion contains 18 electrons:
a) State the period and the group of the periodic table that element N belongs.
b) Write the formula of the compound which would be formed if N reacts with bromine.
Date posted: February 26, 2019
- When 27.8g of hydrated aluminium oxide, Al2O3.xH2O, was heated to a constant mass, 20.6g of aluminium oxide was obtained. Determine the value of x (H=1, O=16, A=27)
When 27.8g of hydrated aluminium oxide, Al2O3.xH2O, was heated to a constant mass, 20.6g of aluminium oxide was obtained. Determine the value of x (H=1, O=16, A=27)
Date posted: February 26, 2019
- 6g of iron reacted with hydrogen chloride gas to form iron (II) chloride at S.T.P. Calculate the volume of the hydrogen chloride
gas used. (Fe=56, molar gas volume at S.T.P=22.4dm3 )
6g of iron reacted with hydrogen chloride gas to form iron (II) chloride at S.T.P. Calculate the volume of the hydrogen chloride
gas used. (Fe=56, molar gas volume at S.T.P=22.4dm3 )
Date posted: February 26, 2019
- Study the information in the table below and answer the questions that follow.
Study the information in the table below and answer the questions that follow.
![org12622019139.png](https://www.kenyaplex.com/videolessons/uploads/org12622019139.png)
i) Write the general formula of the hydrocarbons in the table.
ii) Predict the relative molecular mass of the hydrocarbon with 5 carbon atoms.
iii) Determine the molecular formula of the hydrocarbon in (II) above and draw its structural formula (H=1.0, C = 12.0)
Date posted: February 26, 2019
- An organic compound contains 24.24% carbon 4.04% hydrogen and the rest is chlorine
a) Find its empirical formula. (C=12, H=1, Cl=35.5)
b) Find its molecular formula if its R.M.M is 99.
An organic compound contains 24.24% carbon 4.04% hydrogen and the rest is chlorine
a) Find its empirical formula. (C=12, H=1, Cl=35.5)
b) Find its molecular formula if its R.M.M is 99.
Date posted: February 26, 2019
- Using dots (.) and crosses (x) to represent outermost electrons, draw diagrams to show bonding in.
a)Carbon (IV) oxide
b) NH4+
Using dots (.) and crosses (x) to represent outermost electrons, draw diagrams to show bonding in.
a)Carbon (IV) oxide
b) NH4+
Date posted: February 26, 2019