A molecule with two atoms and no lone pairs around the central atom has a shape.
A molecule with four atoms and no lone pairs around the central atom has a
shape.
A molecule that has two atoms and two lone pairs around the central atom has a
shape.
A molecule that has five atoms and no lone pairs around the central atom has a
shape.
DONE

linear

tetrahedral

bent

trigonal bipyramidal

Explanation:

When there are two atoms around the central atom and no lone pair of electrons, the number of electron pairs will be 2  that means the hybridization will be sp and the electronic geometry of the molecule will be linear.

When there are four atoms around the central atom and no lone pair of electrons, the number of electron pairs will be 4  that means the hybridization will be and the electronic geometry of the molecule will be tetrahedral.

When there are two atoms around the central atom and two lone pair of electrons, the number of electron pairs will be 4  that means the hybridization will be and the electronic geometry of the molecule will be bent.

When there are five atoms around the central atom and no lone pair of electrons, the number of electron pairs will be 5 that means the hybridization will be and the electronic geometry of the molecule will be trigonal bipyramidal.

when 25.0 ml of 0.700 mol/l naoh was mixed in a calorimeter with 25.0 ml of 0.700 mol/l hcl, both initially at 20.0 °c, the temperature increased to 22.1 °c. the heat capacity of the calorimeter is 279 j/°c.

the equation for the reaction is:

naoh + hcl → nacl + h₂o

moles of hcl = 0.0250 l hcl ×

0.700

mol hcl

1 l hcl = 0.0175 mol hcl

volume of solution = (25.0 + 25.0) ml = 50.0 ml

mass of solution = 50.0 ml soln ×

1.00

ml soln

= 50.0 g soln

δt=t2-t1

= (22.1 – 20.0) °c = 2.1 °c

the heats involved are

heat from neutralization + heat to warm solution + heat to warm calorimeter = 0

q1+q2+q3=0

nδh+mcδt+cδt=0

0.0175 mol ×

δh

+ 50.0 g × 4.184 j·g⁻¹°c⁻¹ × 2.1 °c + 279 j°c⁻¹ × 2.1 °c = 0

0.0175 mol ×

δh

+ 439.32 j + 585.9 j = 0

0.0175 mol ×

δh

= -1025.22 j

δh=1025.22j0.0175 mol= -58 600 j/mol = -58.6 kj/mol

the major pests we deal with are insects, weeds and fungal diseases. a pesticide is a product, whether organic or chemical, used to kill the target pest. there are other techniques gardeners should use that can prevent the severe infestations that make the use of pesticides necessary